--_OVID_emlbndry_WKHLTH Content-Type: text/plain <1> UI - 873DS-0001 DD - ISI Document Solution: 873DS AU - Lill H AU - Hisabori T AU - Groth G AU - Bald D MA - dirk.bald@falw.vu.nl RA - Bald D TI - A thermostable enzyme as an experimental platform to study properties of less stable homologues SO - Protein Engineering, Design & Selection. 17(7):553-555, 2004 Jul. AS - Protein Eng. Des. Sel 2004 Jul;17(7):553-555 PU - OXFORD UNIV PRESS, GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND. URL: http://www.oup.co.uk IS - 1741-0126 MH - Chimeric enzyme MH - Protein assembly MH - Protein engineering MH - Protein stability. MH - Atp synthase MH - Gamma-subunit MH - Escherichia-coli MH - Chloroplast f-1-atpase MH - Biomolecular motor MH - Sequence MH - Tentoxin MH - Subcomplex MH - Nanodevice MH - Resolution. AB - The structural and functional characterization of proteins is frequently hampered by lack of stability or by insufficient assembly of oligomeric proteins in over-expression systems. Using F-1-ATPase as a case study, we tackled this problem by introducing function-determining domains from a difficult-to-handle variety of an enzyme into a stable homologue. [References: 28] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Biochemistry & Biophysics in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Bald D Fac Earth & Life Sci, Dept Biol Struct De Boelelaan 1085 NL-1081 HV Amsterdam Netherlands Fac Earth & Life Sci, Dept Biol Struct NL-1081 HV Amsterdam Netherlands Tokyo Inst Technol, Chem Resources Lab Yokohama Kanagawa 2268503 Japan Univ Dusseldorf, Dept Plant Biochem D-40225 Dusseldorf Germany <2> UI - 872DQ-0009 DD - ISI Document Solution: 872DQ AU - Ohara K AU - Kokado Y AU - Yamamoto H AU - Sato F AU - Yazaki K MA - yazaki@rish.kyoto-u.ac.jp RA - Yazaki K TI - Engineering of ubiquinone biosynthesis using the yeast coq2 gene confers oxidative stress tolerance in transgenic tobacco SO - Plant Journal. 40(5):734-743, 2004 Dec. AS - Plant J 2004 Dec;40(5):734-743 PU - BLACKWELL PUBLISHING LTD, 9600 GARSINGTON RD, OXFORD OX4 2DG, OXON, ENGLAND. URL: http://www.blackwell-science.com IS - 0960-7412 MH - Metabolic engineering MH - Oxidative stress MH - P-hydroxybenzoate MH - Polyprenyltransferase MH - Subcellular localization MH - Tobacco MH - Ubiquinone. MH - Electron-transport MH - Lithospermum-erythrorhizon MH - Photooxidative stress MH - Coenzyme q(10) MH - Rat-liver MH - Ubia gene MH - Plants MH - Arabidopsis MH - Antioxidant MH - Expression. AB - Ubiquinone (UQ), an electron carrier in the respiratory chain ranging from bacteria to humans, shows antioxidative activity in vitro, but its physiological role in vivo is not yet clarified in plants. UQ biosynthesis was modified by overexpressing the yeast gene coq2, which encodes p-hydroxybenzoate:polyprenyltransferase, to increase the accumulation of UQ-6 in yeast and UQ-10 in tobacco. The yeast and tobacco transgenic lines showed about a three- and six-fold increase in UQ, respectively. COQ2 polypeptide, the localization of which was forcibly altered to the endoplasmic reticulum, had the same or a greater effect as mitochondria-localized COQ2 on the increase in UQ in both the yeast and tobacco transformants, indicating that the UQ intermediate is transported from the endoplasmic reticulum to the mitochondria. Plants with a high UQ level are more resistant to oxidative stresses caused by methyl viologen or high salinity. This is attributable to the greater radical scavenging ability of the transgenic lines when compared with the wild type. [References: 40] LG - English PT - Article SB - Current Contents(R)/Agriculture, Biology & Environmental Sciences Current Contents(R)/Life Sciences CC - Plant Sciences in Current Contents(R)/Agricultural, Biology & Environmental Sciences. Animal & Plant Sciences in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Yazaki K Kyoto Univ, Res Inst Sustainable Humanosphere, Lab Plant Gene Express Kyoto 6110011 Japan Kyoto Univ, Res Inst Sustainable Humanosphere, Lab Plant Gene Express Kyoto 6110011 Japan Kyoto Univ, Grad Sch Biostudies, Div Integrated Life Sci, Lab Mol & Cellular Biol Totipotency Kyoto 6068502 Japan Toyo Univ, Fac Life Sci Gunma 3740193 Japan <3> UI - 873SA-0002 DD - ISI Document Solution: 873SA AU - Cleavitt N MA - nlc4@cornell.edu RA - Cleavitt N TI - Comparative ecology of a lowland and a subalpine species of Mnium in the northern Rocky Mountains SO - Plant Ecology. 174(2):205-216, 2004. AS - Plant Ecol 2004;174(2):205-216 PU - KLUWER ACADEMIC PUBL, VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS. URL: http://www.wkap.nl IS - 1385-0237 MH - Altitudinal limit MH - Establishment MH - M. arizonicum MH - M. spinulosum MH - Transplant. MH - Geum-urbanum l MH - Altitudinal distribution MH - Chlorophyll fluorescence MH - Positive interactions MH - Grimmia-pulvinata MH - Rivale l MH - Temperature MH - Mosses MH - Plants MH - Photosynthesis. AB - Factors that set the altitudinal limits of plants have been relatively well explored for many land plant groups, but not for bryophytes. Bryophytes typically represent a significant portion of alpine floras with many species specific to highland systems. Differences between highland and lowland bryophytes have been underinvestigated. In the present study spanning three growing seasons, a subalpine and a lowland moss were both reciprocally planted as apical fragments and transplanted as adults between sites at 1400 m and 2000 m in the Front Ranges of the Rocky Mountains, Alberta. The lowland species, Mnium spinulosum, was less tolerant of conditions at 2000 m than the subalpine species, M. arizonicum, was to conditions at 1400 m. In particular, M. spinulosum had lower establishment from both apical fragments and spores at higher elevation sites. Both species had significantly lower establishment during the abnormally cold growing season of 1999, but fragments of M. arizonicum were better able to adjust their investment in establishment. The effect of a dominant feather moss, Hylocomium splendens, on establishment and transplant health was tested for M. arizonicum. Establishment of M. arizonicum was lower in Hylocomium mats than on bare humus regardless of site elevation suggesting allelopathy; however, stem survival in adult transplants was higher in Hylocomium mats than in Mnium dominated microsites at the higher elevation suggesting facilitation. Competition, rather than a lack of physiological plasticity, probably determines the lower elevation limit of the subalpine moss, while poor establishment ability at low temperatures accounts for the upper elevation limit of the montane moss. [References: 46] LG - English PT - Article SB - Current Contents(R)/Agriculture, Biology & Environmental Sciences CC - Environment/Ecology in Current Contents(R)/Agricultural, Biology & Environmental Sciences. EW - 2005 week 01 IN - Reprint available from: Cleavitt N Cornell Univ, Dept Nat Resources 8F Fernow Hall Ithaca, NY 14853 USA Cornell Univ, Dept Nat Resources Ithaca, NY 14853 USA <4> UI - 872DY-0002 DD - ISI Document Solution: 872DY AU - Zotz G AU - Enslin A AU - Hartung W AU - Ziegler H MA - gerhard.zotz@unibas.ch RA - Zotz G TI - Physiological and anatomical changes during the early ontogeny of the heteroblastic bromeliad, Vriesea sanguinolenta, do not concur with the morphological change from atmospheric to tank form SO - Plant, Cell & Environment. 27(11):1341-1350, 2004 Nov. AS - Plant Cell Environ 2004 Nov;27(11):1341-1350 PU - BLACKWELL PUBLISHING LTD, 9600 GARSINGTON RD, OXFORD OX4 2DG, OXON, ENGLAND. URL: http://www.blackwell-science.com IS - 0140-7791 MH - Abscisic acid MH - Heteroblasty MH - Intraspecific variability MH - Leaf nitrogen MH - Ontogenetic drift MH - Photosynthesis MH - Phyllotaxis MH - Specific leaf area MH - Vascular epiphytes MH - Water relations. MH - Tillandsia-deppeana bromeliaceae MH - Plant size MH - Ecophysiological consequences MH - Vascular epiphytes MH - Abscisic-acid MH - Juvenile MH - Water MH - Tolerance. AB - Two distinct morphological forms characterize the ontogeny of many epiphytic bromeliads. Smaller plants exhibit an atmospheric habit, while larger plants form water-impounding tanks. The study of the functional significance of heteroblasty in epiphytes is severely hampered by considerable size-related variation in morphological, anatomical and physiological parameters. To overcome this problem, plants of varying size of both atmospheric and tank form were included in the present study with Vriesea sanguinolenta. The results show that virtually all morphological, anatomical and physiological characteristics vary during ontogeny, but changes were rarely directly related to the step change in gross morphology. Changes were either: (1) gradual from smallest atmospheric to small tank (e.g. leaf divergence angles, reduction in photosystem II efficiency during drought, speed of recovery after drought); (2) there was no change between atmospheric and small tank, but a gradual or step change within the tank form (stomatal density, relationship of leaf N and specific leaf area); or (3) developmental patterns were more complicated with decreases and increases during ontogeny (photosynthetic capacity, carbon isotope ratios, abscisic acid levels during drought). Although the comparisons between ontogenetic phases were always confounded by size differences, a hypothetical small tank plant is expected to suffer higher water loss than a real atmospheric, whereas a hypothetical, large atmospheric plant would show reduced access to resources, such as nutrients, in comparison with the real tank. The present results are consistent with the notion of heteroblasty as an adaptation of early ontogenetic stages to drought, but highlight that size-related variation greatly modifies any difference directly associated with the step change from atmospheric to tank. [References: 38] LG - English PT - Article SB - Current Contents(R)/Agriculture, Biology & Environmental Sciences Current Contents(R)/Life Sciences CC - Plant Sciences in Current Contents(R)/Agricultural, Biology & Environmental Sciences. Animal & Plant Sciences in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Zotz G Univ Basel, Inst Bot Schonbeinstr 6 CH-4056 Basel Switzerland Univ Basel, Inst Bot CH-4056 Basel Switzerland Smithsonian Trop Res Inst Balboa Panama Univ Wurzburg, Lehrstuhl Bot 2 D-97082 Wurzburg Germany Univ Wurzburg, Lehrstuhl Bot 1 D-8700 Wurzburg Germany Tech Univ Munich, Lehrstuhl Bot D-85354 Freising Weihenstephan Germany <5> UI - 872DY-0010 DD - ISI Document Solution: 872DY AU - Kubien DS AU - Sage RF MA - dkubien@massey.ac.nz RA - Kubien DS TI - Dynamic photo-inhibition and carbon gain in a C-4 and a C-3 grass native to high latitudes SO - Plant, Cell & Environment. 27(11):1424-1435, 2004 Nov. AS - Plant Cell Environ 2004 Nov;27(11):1424-1435 PU - BLACKWELL PUBLISHING LTD, 9600 GARSINGTON RD, OXFORD OX4 2DG, OXON, ENGLAND. URL: http://www.blackwell-science.com IS - 0140-7791 MH - C-4 plants MH - Cool-climates MH - Photo-inhibition MH - Photoprotection MH - Quantum yield. MH - Miscanthus x giganteus MH - Young zea-mays MH - Low-temperature MH - Chlorophyll fluorescence MH - Growth temperature MH - Quantum yield MH - Maize leaves MH - Photosynthetic performance MH - Microsite characteristics MH - Chilling damage. AB - C-4 plants are rare in the cool climates characteristic of high latitudes and altitudes, perhaps because of an enhanced susceptibility to photo-inhibition at low temperatures relative to C-3 species. In the present study we tested the hypothesis that low-temperature photo-inhibition is more detrimental to carbon gain in the C-4 grass Muhlenbergia glomerata than the C-3 species Calamogrostis Canadensis. These grasses occur together in boreal fens in northern Canada. Plants were grown under cool (14/10 degreesC day/night) and warm (26/22 degreesC) temperatures before measurement of the light responses of photosynthesis and chlorophyll fluorescence at different temperatures. Cool growth temperatures led to reduced rates of photosynthesis in M. glomerata at all measurement temperatures, but had a smaller effect on the C-3 species. In both species the amount of xanthophyll cycle pigments increased when plants were grown at 14/10 degreesC, and in M. glomerata the xanthophyll epoxidation state was greatly reduced. The detrimental effect of low growth temperature on photosynthesis in M. glomerata was almost completely reversed by a 24-h exposure to the warm-temperature regime. These data indicate that reversible dynamic photo-inhibition is a strategy by which C-4 species may tolerate cool climates and overcome the Rubisco limitation that is prevalent at low temperatures in C-4 plants. [References: 49] LG - English PT - Article SB - Current Contents(R)/Agriculture, Biology & Environmental Sciences Current Contents(R)/Life Sciences CC - Plant Sciences in Current Contents(R)/Agricultural, Biology & Environmental Sciences. Animal & Plant Sciences in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Kubien DS Massey Univ, Inst Mol Biosci Private Bag 11 222 Palmerston North New Zealand Univ Toronto, Dept Bot Toronto ON M5S 3B2 Canada <6> UI - 870VF-0007 DD - ISI Document Solution: 870VF AU - Okamoto T AU - Higuchi K AU - Shinkawa T AU - Isobe T AU - Lorz H AU - Koshiba T AU - Kranz E MA - okamoto-takashi@c.metro-u.ac.jp RA - Okamoto T TI - Identification of major proteins in maize egg cells SO - Plant & Cell Physiology. 45(10):1406-1412, 2004 Oct. AS - Plant Cell Physiol 2004 Oct;45(10):1406-1412 PU - OXFORD UNIV PRESS, GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND. URL: http://www.oup.co.uk IS - 0032-0781 MH - Annexin MH - Egg cell MH - Glycolysis MH - Major protein MH - Mass spectrometry. MH - In-vitro fertilization MH - Flowering plants MH - Mitochondria MH - Annexins MH - Single MH - Glycolysis MH - Translocator MH - Protoplasts MH - Arabidopsis MH - Exocytosis. AB - In most flowering plants, the female gametophyte develops in an ovule deeply embedded in the ovary. Through double fertilization, the egg cell fuses with the sperm cell, resulting in a zygote, which develops into the embryo. In the present study, we analyzed egg cell lysates by polyacrylamide gel electrophoresis and subsequent mass spectrometry-based proteomics technology, and identified major protein components expressed in the egg cell. The identified proteins included three cytosolic enzymes of the glycolytic pathway, glyceraldehyde-3-phosphate dehydrogenase, 3-phosphoglycerate kinase and triosephosphate isomerase, two mitochondrial proteins, the ATP synthase beta-subunit and an adenine nucleotide transporter, and annexin p35. In addition, expression levels of these proteins in the egg cell were compared with those in the early embryo, the central cell and the suspension cell. Annexin p35 was highly expressed only in the egg cell, and glyceraldehyde-3-phosphate dehydrogenase, 3-phosphoglycerate kinase and the adenine nucleotide transporter were expressed at higher levels in egg cells than in central and cultured cells. These results indicate that annexin p35 in the egg cell and zygote is involved in the exocytosis of cell wall materials, which is induced by a fertilization-triggered increase in cytosolic Ca2+ levels, and that the egg cell is rich in an enzyme subset for the energy metabolism. [References: 34] LG - English PT - Article SB - Current Contents(R)/Agriculture, Biology & Environmental Sciences Current Contents(R)/Life Sciences CC - Plant Sciences in Current Contents(R)/Agricultural, Biology & Environmental Sciences. Animal & Plant Sciences in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Okamoto T Tokyo Metropolitan Univ, Dept Sci Biol Minami Osawa 1-1 Tokyo 1920397 Japan Tokyo Metropolitan Univ, Dept Sci Biol Tokyo 1920397 Japan Univ Hamburg, Biozentrum Klein Flottbek D-22609 Hamburg Germany Univ Hamburg, Bot Garten D-22609 Hamburg Germany Tokyo Metropolitan Univ, Dept Chem Tokyo 1920397 Japan <7> UI - 870VF-0009 DD - ISI Document Solution: 870VF AU - Miyake C AU - Shinzaki Y AU - Miyata M AU - Tomizawa K MA - cmiyake@rite.or.jp RA - Miyake C TI - Enhancement of cyclic electron flow around PSI at high light and its contribution to the induction of non-photochemical quenching of chl fluorescence in intact leaves of tobacco plants SO - Plant & Cell Physiology. 45(10):1426-1433, 2004 Oct. AS - Plant Cell Physiol 2004 Oct;45(10):1426-1433 PU - OXFORD UNIV PRESS, GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND. URL: http://www.oup.co.uk IS - 0032-0781 MH - Chl fluorescence MH - Cyclic electron flow MH - Non-photochemical quenching (npq) photosynthesis MH - P700 MH - Psi. MH - Pyridine-nucleotide dehydrogenase MH - Singlet oxygen production MH - Transgenic potato plants MH - Water-water cycle MH - Photosystem-ii MH - Chlorophyll fluorescence MH - Intersystem chain MH - Violaxanthin deepoxidation MH - Spinach-chloroplasts MH - Thylakoid membranes. AB - Non-photochemical quenching (NPQ) of Chi fluorescence is a mechanism for dissipating excess photon energy and is dependent on the formation of a DeltapH across the thylakoid membranes. The role of cyclic electron flow around photosystem I (PSI) (CEF-PSI) in the formation of this DeltapH was elucidated by studying the relationships between O-0-evolution rate [V(O-2)], quantum yield of both PSII and PSI [(D(PSII) and (D(PSI)], and Chi fluorescence parameters measured simultaneously in intact leaves of tobacco plants in CO2-saturated air. Although increases in light intensity raised V(O-2) and the relative electron fluxes through both PSII and PSI [Phi(PSII)xPFD and Phi(PSI)xPFD] only Phi(PSI)xPFD continued to increase after V(O-2) and Phi(PSII)xPFD became light saturated. These results revealed the activity of an electron transport reaction in PSI not related to photosynthetic linear electron flow (LEF), namely CEF-PSI. NPQ of Chi fluorescence drastically increased after Phi(PSII)xPFD became light saturated and the values of NPQ correlated positively with the relative activity of CEF-PSI. At low temperatures, the light-saturation point of (D(PSII)xPFD was lower than that of Phi(PSI)xPFD and NPQ was high. On the other hand, at high temperatures, the light-dependence curves of Phi(PSII)xPFD and Phi(PSI)xPFD corresponded completely and NPQ was not induced. These results indicate that limitation of LEF induced CEF-PSI, which, in turn, helped to dissipate excess photon energy by driving NPQ of Chi fluorescence. [References: 58] LG - English PT - Article SB - Current Contents(R)/Agriculture, Biology & Environmental Sciences Current Contents(R)/Life Sciences CC - Plant Sciences in Current Contents(R)/Agricultural, Biology & Environmental Sciences. Animal & Plant Sciences in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Miyake C RITE 9-2 Kizugawadai Kyoto 6190292 Japan RITE Kyoto 6190292 Japan <8> UI - 871UE-0010 DD - ISI Document Solution: 871UE AU - Rousseaux MC AU - Flint SD AU - Searles PS AU - Caldwell MM MA - sflint@cc.usu.edu RA - Flint SD TI - Plant responses to current solar ultraviolet-B radiation and to supplemented solar ultraviolet-B radiation simulating ozone depletion: An experimental comparison SO - Photochemistry & Photobiology. 80(2):224-230, 2004 Sep-Oct. AS - Photochem. Photobiol 2004 Sep-Oct;80(2):224-230 PU - AMER SOC PHOTOBIOLOGY, BIOTECH PARK, 1021 15TH ST, SUITE 9, AUGUSTA, GA 30901-3158 USA. URL: http://www.kumc.edu/POL IS - 0031-8655 MH - Spectral weighting functions MH - Uv-b MH - Chlorophyll fluorescence MH - Vascular plants MH - Dna-damage MH - Field MH - Growth MH - Ambient MH - Photosynthesis MH - Ecosystem. AB - Field experiments assessing UV-B effects on plants have been conducted using two contrasting techniques: supplementation of solar UV-B with radiation from fluorescent UV lamps and the exclusion of solar UV-B with filters. We compared these two approaches by growing lettuce and oat simultaneously under three conditions: UV-B exclusion, near-ambient UV-B (control) and UV-B supplementation (simulating a 30% ozone depletion). This permitted computation of "solar UV-B" and "supplemental UV-B" effects. Microclimate and photosynthetically active radiation were the same under the two treatments and the control. Excluding UV-B changed total UV-B radiation more than did supplementing UV-B, but the UV-B supplementation contained more "biologically effective" shortwave radiation. For oat, solar UV-B had a greater effect than supplemental UV-B on main shoot leaf area and main shoot mass, but supplemental UV-B had a greater effect on leaf and tiller number and UV-B-absorbing compounds. For lettuce, growth and stomatal density generally responded similarly to both solar UV-B and supplemented UV-B radiation, but UV-absorbing compounds responded more to supplemental UV-B, as in oat. Because of the marked spectral differences between the techniques, experiments using UV-B exclusion are most suited to assessing effects of present-day UV-B radiation, whereas UV-B supplementation experiments are most appropriate for addressing the ozone depletion issue. [References: 47] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Biochemistry & Biophysics in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Flint SD Utah State Univ, Dept Forest Range & Wildlife Sci 5230 Old Main Hill Logan, UT 84322 USA Utah State Univ, Dept Forest Range & Wildlife Sci Logan, UT 84322 USA Consejo Nacl Invest Cient & Tecn, Inst Invest Fisiol & Ecol Vinculadas Agr Buenos Aires DF Argentina Univ Buenos Aires Buenos Aires DF Argentina <9> UI - 871UE-0026 DD - ISI Document Solution: 871UE AU - Han RM AU - Wu YS AU - Feng J AU - Ai XC AU - Zhang JP AU - Skibsted LH MA - jpzhang@mail.iccas.ac.cn RA - Zhang JP TI - Radical cation generation from singlet and triplet excited states of all-trans-lycopene in chloroform SO - Photochemistry & Photobiology. 80(2):326-333, 2004 Sep-Oct. AS - Photochem. Photobiol 2004 Sep-Oct;80(2):326-333 PU - AMER SOC PHOTOBIOLOGY, BIOTECH PARK, 1021 15TH ST, SUITE 9, AUGUSTA, GA 30901-3158 USA. URL: http://www.kumc.edu/POL IS - 0031-8655 MH - Resolved absorption-spectroscopy MH - Photoinduced electron-transfer MH - Raman excitation profiles MH - Beta-carotene MH - Rhodobacter-sphaeroides MH - Vibrational-relaxation MH - Energy-transfer MH - Lh2 complexes MH - S-1 state MH - Dynamics. AB - On direct photoexcitation, subpicosecond time-resolved absorption spectroscopy revealed that the 1B(u)-type singlet excited state of all-trans-lycopene in chloroform was about seven times more efficient than all-trans-beta-carotene in generating the radical cation. The time constant of radical cation generation from the 1B(u)-type state was found to be similar to0.14 ps, a value that was comparable for the two carotenoids. On anthracene-sensitized triplet excitation, radical cation generation was found to be much less efficient for lycopene than for beta-carotene. A slow rising phase (20-30 mus) in the bleaching of ground-state absorption was common for both lycopene and beta-carotene in chloroform and was ascribed to an efficient secondary reaction with a solvent radical leading to the formation of carotenoid radical cations. The reverse ordering in the tendency of the excited states of different multiplicities for the two carotenoids to generate radical cations is discussed in relation to the two carotenoids as scavengers of free radicals. [References: 42] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Biochemistry & Biophysics in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Zhang JP Chinese Acad Sci, State Key Lab Struct Chem Unstable & Stable Speci, Inst Chem 1st North St Beijing 100080 Peoples R China Chinese Acad Sci, State Key Lab Struct Chem Unstable & Stable Speci, Inst Chem Beijing 100080 Peoples R China Royal Vet & Agr Univ, Dept Dairy & Food Sci Frederiksberg C Denmark <10> UI - 871PB-0013 DD - ISI Document Solution: 871PB AU - Tang CY AU - Yip HS AU - Poon MY AU - Yau WL AU - Yap MKH MA - orcytang@polyu.edu.hk RA - Tang CY TI - Macular pigment optical density in young Chinese adults SO - Ophthalmic & Physiological Optics. 24(6):586-593, 2004 Nov. AS - Ophthalmic Physiol. Opt 2004 Nov;24(6):586-593 PU - BLACKWELL PUBLISHING LTD, 9600 GARSINGTON RD, OXFORD OX4 2DG, OXON, ENGLAND. URL: http://www.blackwell-science.com IS - 0275-5408 MH - Chinese MH - Macular pigment MH - Optical density MH - Heterochromatic photometry. MH - Age-related maculopathy MH - Heterochromatic flicker photometry MH - Lutein supplementation MH - Spatial-distribution MH - Primate retinas MH - Older subjects MH - Degeneration MH - Zeaxanthin MH - Carotenoids MH - Autofluorescence. AB - Purpose: The purpose of this study was to determine the macular pigment optical density (MPOD) in a group of Chinese subjects using a simple customized light emitting diode-based device. Methods: Heterochromatic flicker photometry was used in this study. With a 1degrees diameter circular test stimulus, MPOD was estimated by comparing the relative sensitivities to a blue light, against a green reference, between foveal and parafoveal 4degrees temporal locations. Fixed alternating frequencies were used. Repeatability was determined on a small group of subjects. A further group of 67 young healthy subjects provided data for MPOD norms. Results: All results were corrected to the common MPOD reference wavelength of 460 nm. The group-averaged MPOD was 0.48 (S.D. 0.23). We found no gender difference in MPOD. The coefficient of variability was 7.2-8.0% and the coefficient of repeatability was 0.12. Conclusions: The MPOD of Chinese subjects did not differ greatly from the reported MPOD in white subjects. [References: 59] LG - English PT - Article SB - Current Contents(R)/Clinical Medicine CC - Ophthalmology in Current Contents(R)/Clinical Medicine. EW - 2005 week 01 IN - Reprint available from: Tang CY Hong Kong Polytech Univ, Dept Optometry & Radiog Kowloon Hong Kong Peoples R China Hong Kong Polytech Univ, Dept Optometry & Radiog Kowloon Hong Kong Peoples R China <11> UI - 870HL-0004 DD - ISI Document Solution: 870HL AU - Jang JS AU - Cho HY AU - Lee YJ AU - Ha WS AU - Kim HW MA - jsjang@nongae.gsnu.ac.kr RA - Jang JS TI - The differential proteome profile of stomach cancer: Identification of the biomarker candidates SO - Oncology Research. 14(10):491-499, 2004. AS - Oncol. Res 2004;14(10):491-499 PU - COGNIZANT COMMUNICATION CORP, 3 HARTSDALE ROAD, ELMSFORD, NY 10523-3701 USA. URL: http://www.cognizantcommunication.com/ IS - 0965-0407 MH - Stomach cancer MH - Proteome MH - Biomarker. MH - Gastric-cancer MH - Expression MH - Proteins MH - Genes MH - Methyltransferase MH - 14-3-3-proteins MH - Adenocarcinoma MH - Proliferation MH - Prohibitin MH - Apoptosis. AB - By comparative proteome analysis we searched for characteristic alterations of human stomach adenocarcinoma tissue and paired surrounding normal tissue. Selected differential protein spots were identified with peptide mass fingerprinting based on matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF) and database searching. We identified protein alterations in 18 stomach cancer tissues compared with normal controls, comprising elevated levels of eight proteins, including 14-3-3 zeta, calcyclin, keratin, apolipoprotein A-1 precursor, proteasome activator complex subunit, nucleoside diphosphate kinase, nicotinanride N-methyltransferase, and pyridoxal kinase. Five proteins (CA11, prohibitin, peroxiredoxin 4, serum amyloid P component, and NADH-ubiquinone oxidoreductase 23 kDa subunit) were decreased. These data are valuable for identification of differentially expressed proteins involved in stomach cancer carcinogenesis, providing biomarker candidates to develop diagnostic and therapeutic tools. [References: 26] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Oncogenesis & Cancer Research in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Jang JS GyeongSang Natl Univ Hosp, Dept Internal Med 90 Chiram Dong Jinju 660702 South Korea GyeongSang Natl Univ, Coll Med, Dept Internal Med Jinju South Korea GyeongSang Natl Univ, Coll Med, Dept Surg Jinju South Korea GyeongSang Natl Univ, Coll Med, Dept Pathol Jinju South Korea GyeongSang Inst Hlth Sci Jinju South Korea <12> UI - 871EY-0041 DD - ISI Document Solution: 871EY AU - Gattermann N AU - Dadak M AU - Hofhaus G AU - Wulfert M AU - Berneburg M AU - Loeffler ML AU - Simmonds HA RA - Gattermann N TI - Severe impairment of nucleotide synthesis through inhibition of mitochondrial respiration SO - Nucleosides, Nucleotides & Nucleic Acids. 23(8-9):1275-1279, 2004 Oct. AS - Nucleosides Nucleotides Nucleic Acids 2004 Oct;23(8-9):1275-1279 PU - MARCEL DEKKER INC, 270 MADISON AVE, NEW YORK, NY 10016 USA. URL: http://www.dekker.com IS - 1525-7770 MH - Pyrimidine nucleotide synthesis MH - Dehydroorotic acid dehydrogenase MH - Mitochondrial respiratory chain MH - Respiratory chain defect MH - Mitochondrial dna mutations MH - Myelodysplastic syndromes. MH - Dna. AB - Since de-novo synthesis of pyrimidine nucleotides is coupled to the mitochondrial respiratory chain (RC) via dehydroorotic acid dehydrogenase (DHODH), respiratory chain dysfunction should impair pyrimidine synthesis. To investigate this, we used specific RC inhibitors, Antimycin A and Rotenone, to treat primary human keratinocytes and 143B cells, a human osteosarcoma cell line, in culture. This resulted in severe impairment of de novo pyrimidine nucleotide synthesis. The effects of RC inhibition were not restricted to pyrimidine synthesis, but concerned purine nucleotides, too. While the total amount of purine nucleotides was not diminished, they were significantly broken down from triphosphates to monophosphates, reflecting impaired mitochondrial ATP regeneration. The effect of Rotenone was similar to that of Antimycin A. This was surprising since Rotenone inhibits complex I of the respiratory chain, which is upstream of ubiquinone where DHODH interacts with the RC. In order to avoid unspecific effects of Rotenone, we examined the consequences of a mitochondrial DNA mutation that causes a specific complex I defect. The effect was much less pronounced than with Rotenone, suggesting that complex I inhibiton cannot fully explain the marked effect of Rotenone on pyrimidine nucleotide synthesis. [References: 6] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Biochemistry & Biophysics in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Gattermann N Univ Dusseldorf, Dept Hematol Oncol & Clin Immunol D-40225 Dusseldorf Germany Univ Dusseldorf, Dept Hematol Oncol & Clin Immunol D-40225 Dusseldorf Germany Univ Dusseldorf, Inst Biochem D-40225 Dusseldorf Germany Univ Dusseldorf, Dept Dermatol D-40225 Dusseldorf Germany Univ Marburg, Inst Physiol Chem D-3550 Marburg Germany Guys Hosp, Purine Res Unit London SE1 9RT England <13> UI - 871NW-0014 DD - ISI Document Solution: 871NW AU - Isaev NK AU - Stelmashook EV AU - Ruscher K AU - Andreeva NA AU - Zorov DB MA - zorov@genebee.msu.su RA - Zorov DB TI - Menadione reduces rotenone-induced cell death in cerebellar granule neurons SO - Neuroreport. 15(14):2227-2231, 2004 Oct 5. AS - Neuroreport 2004 Oct 5;15(14):2227-2231 PU - LIPPINCOTT WILLIAMS & WILKINS, 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA. URL: http://www.lww.com/ IS - 0959-4965 MH - Cell culture MH - Cerebellar granule neuron MH - Cerebral ischemia MH - Chemical hypoxia MH - Free radicals MH - Menadione MH - Mitochondria. MH - Mitochondrial permeability transition MH - Electron-transport MH - Respiratory-chain MH - Complex-i MH - Inhibition MH - Disease MH - Neurotoxicity MH - Oxidation MH - Cultures MH - System. AB - Oxidative stress has been implicated in neuronal death caused by cerebral ischemia or some neurologic disorders. Chemical hypoxia (term defining the simulation by using respiratory inhibitors) chosen as in vitro ischemic model, was induced in primary cultures of rat cerebellar granule neurons by inhibitors of mitochondrial electron transport such as rotenone or paraquat (complex I), 3-nitropropionic acid (3-NPA, complex II), antimycin A (complex III), or sodium azide (complex IV). All compounds caused neuronal death determined by trypan blue staining and MTT-test. On the other hand, neurotoxicity of rotenone and paraquat but not of 3-NPA, antimycin or azide was significantly abolished by menadione (vitamin K3, 2-methyl-1,4-naphthoquinone). This neuroprotective effect of menadione was associated with a decrease of rotenone-induced free radical production. [References: 24] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Neurosciences & Behavior in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Zorov DB Moscow MV Lomonosov State Univ, AN Belozersky Inst Physicochem Biol, Dept Bioenerget Moscow 119992 Russia Moscow MV Lomonosov State Univ, AN Belozersky Inst Physicochem Biol, Dept Bioenerget Moscow 119992 Russia Russian Acad Med Sci, Inst Brain Res Moscow 105064 Russia Humboldt Univ, Charite Hosp, Dept Neurol D-1086 Berlin Germany <14> UI - 873RY-0008 DD - ISI Document Solution: 873RY AU - Gupta D AU - Arora R AU - Garg AP AU - Bala M AU - Goel HC MA - goelharish@hotmail.com RA - Goel HC TI - Modification of radiation damage to mitochondrial system in vivo by Podophyllum hexandrum: Mechanistic aspects SO - Molecular & Cellular Biochemistry. 266(1-2):65-77, 2004 Nov. AS - Mol. Cell. Biochem 2004 Nov;266(1-2):65-77 PU - KLUWER ACADEMIC PUBL, VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS. URL: http://www.wkap.nl IS - 0300-8177 MH - Electron transport chain MH - Gamma radiation MH - Glutathione MH - Mitochondria MH - Podophyllum hexandrum MH - Radioprotection MH - Superoxide. MH - Rat-liver mitochondria MH - Lipid-peroxidation MH - Gamma-irradiation MH - Glutathione MH - Protection MH - Flavonoids MH - Superoxide MH - Generation MH - Organelles MH - Membranes. AB - The present study was undertaken to investigate whether RP-1 treatment protected mitochondrial system against radiation damage and also to unravel the mechanism associated with this process. Radioprotection of mitochondrial system by Podophyllum hexandrum (RP-1) was investigated to understand its mechanism of action. Levels of superoxide anion (O2-), reduced or oxidized glutathione (GSH or GSSG), thiobarbituric acid reactive substance (TBARS), protein carbonyl (PC), ATP, NADH-ubiquinone oxidoreductase (complex-I), NADH-cytochrome c oxidoreductase (complex I/II), succinate-cytochrome c oxidoreductase (complex II/III) and mitochondrial membrane potential (MMP) were studied in mitochondria isolated from liver of mice belonging to various treatment groups. Whole body gamma-irradiation (10 Gy) significantly (p < 0.01) increased the formation of O2-, PC, and TBARS, upto 24 h as compared to untreated control. RP-1 treatment (200 mg/kg b.w.) to mice 2 h before irradiation reduced the radiation-induced O2- generation within 4 h and formation of TBARS and PC upto 24 h significantly (p < 0.01). Singularly irradiation or RP-1 treatment significantly (p < 0.01) increased the levels of glutathione within an hour, as compared to untreated control. Pre-irradiation administration of RP-1 enhanced levels of GSH induced increase in complex I (upto 16 h), complex I/III (4 h) complex II/III activity (upto 24 h; p < 0.01) and inhibited the radiation-induced decrease in MMP significantly (24 h; p < 0.01). The present study indicates that RP-1 itself modulates several mitichondrial parameters due to its influence on the biochemical milieu within and outside the cells. However, RP-1 treatment before irradiation modulates radiation induced perturbations such as the increase in electron transport chain enzyme activity, formation of O2-, TBARS and PC to offer radioprotection. [References: 42] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Cell & Developmental Biology in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Goel HC Chaudhary Charan Singh Univ, Dept Microbiol Meerut 250005 Uttar Pradesh India Chaudhary Charan Singh Univ, Dept Microbiol Meerut 250005 Uttar Pradesh India Inst Nucl Med & Allied Sci, Div Radiat Biol, Inst Nucl Med & Allied Sci Delhi India <15> UI - 873CT-0006 DD - ISI Document Solution: 873CT AU - Ichikawa H AU - Kokura S AU - Aw TY MA - taw@lsuhsc.edu RA - Aw TY TI - Role of endothelial mitochondria in oxidant production and modulation of neutrophil adherence SO - Journal of Vascular Research. 41(5):432-444, 2004. AS - J. Vasc. Res 2004;41(5):432-444 PU - KARGER, ALLSCHWILERSTRASSE 10, CH-4009 BASEL, SWITZERLAND. URL: http://www.karger.ch IS - 1018-1172 MH - Mitochondria ros generation MH - Neutrophil-endothelial interactions MH - Endothelial cell adhesion molecules MH - Nf kappa b and ap-1 MH - Mitochondrial ros and biphasic neutrophil adhesion response MH - Antimycin a MH - Mitochondrial complex iii MH - Huvec. MH - Hydrogen-peroxide MH - Free-radicals MH - Reactive oxygen MH - Rat-liver MH - Heart-mitochondria MH - Respiratory-chain MH - Complex-iii MH - Generation MH - Cells MH - Adhesion. AB - This study is designed to test whether the postanoxic endothelial mitochondria is an important source of reactive oxygen species (ROS) using a chemical model of mitochondrial disruption to mimic the loss of mitochondrial integrity after anoxia/reoxygenation (A/R). The current objectives were to (1) determine the adhesion of human neutrophils to human umbilical vein endothelial cells exposed to antimycin A, a specific inhibitor of the mitochondrial cytochrome b-c(1) complex, and (2) define the mechanisms responsible for the early and late phases of neutrophil hyperadhesivity. Antimycin A caused a 5-fold increase in ROS generation and induced neutrophil adhesion at 30 min (phase 1) and 4 h (phase 2) that were quantitatively similar to that induced by A/R. Blockade of electron transport in antimycin A and A/R exposed cells with rotenone, amytal or thenoyltrifluoroacetate, but not myxothiazol, prevented neutrophil adhesion, confirming a role for mitochondrial ROS. Catalase inhibited phase 1 adhesion, indicating H2O2 involvement. Anti-ICAM-1 or anti-P-selectin monoclonal antibodies (mAbs) attenuated phase 1 adhesion, while anti-E-selectin mAb attenuated phase 2 adhesion, consistent with roles for constitutive ICAM-1 and preformed P-selectin in early and E-selectin in late phase responses. Actinomycin D and cycloheximide or competing ds-oligonucleotides containing cognate DNA sequences of the nuclear factor kappaB or activator protein-1 attenuated phase 2 adhesion, implicating a role for de novo protein synthesis. Peak surface expression of the endothelial cell adhesion molecules correlated with peak adhesions at phases 1 and 2. These results show that disruption of mitochondrial respiratory chain elicits ROS production that mediates transcription-independent and -dependent surface expression of various adhesion molecules that leads to a two-phase neutrophil-HUVEC interaction similar to that induced by A/R. Copyright (C) 2004 S. Karger AG, Basel. [References: 41] LG - English PT - Article SB - Current Contents(R)/Clinical Medicine Current Contents(R)/Life Sciences CC - Cardiovascular & Respiratory Systems in Current Contents(R)/Clinical Medicine. Cardiovascular & Hematology Research in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Aw TY Louisiana State Univ, Dept Mol & Cellular Physiol, Hlth Sci Ctr 1501 Kings Highway Shreveport, LA 71130 USA Louisiana State Univ, Dept Mol & Cellular Physiol, Hlth Sci Ctr Shreveport, LA 71130 USA <16> UI - 873DO-0008 DD - ISI Document Solution: 873DO AU - Smyth TJ AU - Pemberton KL AU - Aiken J AU - Geider RJ MA - tjsm@pml.ac.uk RA - Smyth TJ TI - A methodology to determine primary production and phytoplankton photosynthetic parameters from Fast Repetition Rate Fluorometry SO - Journal of Plankton Research. 26(11):1337-1350, 2004 Nov. AS - J. Plankton Res 2004 Nov;26(11):1337-1350 PU - OXFORD UNIV PRESS, GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND. URL: http://www.oup.co.uk IS - 0142-7873 MH - Maximum quantum efficiency MH - Equatorial pacific MH - Chlorophyll concentration MH - Active fluorescence MH - Nitrogen limitation MH - Energy-conversion MH - Atlantic-ocean MH - North-atlantic MH - Mixed layer MH - In-situ. AB - Estimating the primary productivity of phytoplankton as they are mixed through the surface layer is often hampered by methodological or conceptual constraints. Fast Repetition Rate Fluorometry (FRRF) allows some of these constraints to be overcome by providing measurements of the instantaneous, depth-dependent rates of primary productivity of phytoplankton in situ. Data acquired by FRR fluorescence is used in this paper to determine the parameters of the photosynthesis-irradiance curve and the instantaneous photosynthetic rates for phytoplankton from the mixed layer during a cruise in the Celtic Sea in May 2000. FRR fluorescence-based estimates of the initial slope of the photosynthesis-light curve (alpha(B)) ranged from 7.5 in well-mixed conditions to 12.7 g C (mol photons)(-1) m(2) (g Chl a)(-1) under stratified conditions. FRR fluorescence-based estimates of the light saturation parameter, E-k, were strongly correlated with the logarithm of the surface PAR. FRR fluorescence-based estimates of the Chl a-specific, light saturated photosynthesis rate (P-m(B)) ranged from 1.4 to 2.8 g C (g Chl a)(-1) h(-1). The FRRF determined values of P-m(B) were consistent with those measured using radiocarbon techniques, however, there were systematic differences when the estimates of alpha(B) and E-k were compared. It was found that 86% of the variance in the instantaneous, integral water column primary productivity determined from FRR fluorescence measurements could be accounted for through a logarithmic relationship to surface PAR indicating that light, rather than nutrient limitation, was the dominant factor influencing photosynthesis. [References: 44] LG - English PT - Article SB - Current Contents(R)/Agriculture, Biology & Environmental Sciences CC - Aquatic Sciences in Current Contents(R)/Agricultural, Biology & Environmental Sciences. EW - 2005 week 01 IN - Reprint available from: Smyth TJ Plymouth Marine Lab Prospect Pl Plymouth PL1 3DH Devon England Plymouth Marine Lab Plymouth PL1 3DH Devon England Univ Essex, Dept Biol Sci Colchester CO4 3SQ Essex England <17> UI - 870SW-0046 DD - ISI Document Solution: 870SW AU - Abramavicius D AU - Zhuang W AU - Mukamel S RA - Mukamel S TI - Peptide secondary structure determination by three-pulse coherent vibrational spectroscopies: A simulation study SO - Journal of Physical Chemistry B. 108(46):18034-18045, 2004 Nov 18. AS - J. Phys. Chem. B 2004 Nov 18;108(46):18034-18045 PU - AMER CHEMICAL SOC, 1155 16TH ST, NW, WASHINGTON, DC 20036 USA. URL: http://pubs.acs.org IS - 1520-6106 MH - 2-dimensional infrared-spectroscopy MH - Femtosecond correlation spectroscopies MH - Picosecond conformational transition MH - X-ray-scattering MH - Rhodobacter-sphaeroides MH - Molecular-dynamics MH - Beta polypeptides MH - Alpha-helix MH - Proteins MH - Spectra. AB - Amide I mode vibrational spectra of four ideal secondary structural motiffs of peptides, alpha helix, 3(10) helix, parallel beta sheet, and antiparallel beta sheet, in response to three infrared pulses with wavevectors k(1), k(2), and k(3) are simulated using a vibrational exciton model. Correlation plots of the signals generated at -k(1) + k(2) + k(3) and +k(1) + k(2) - k(3) show a characteristic peak pattern for each motiff. Resolution is enhanced by applying specific polarization configurations of the optical fields to oriented peptides. [References: 68] LG - English PT - Article SB - Current Contents(R)/Physical, Chemical & Earth Sciences CC - Physical Chemistry/Chemical Physics in Current Contents(R)/Physical, Chemical & Earth Sciences. EW - 2005 week 01 IN - Reprint available from: Mukamel S Univ Calif Irvine, Dept Chem Irvine, CA 92697 USA Univ Calif Irvine, Dept Chem Irvine, CA 92697 USA <18> UI - 871IF-0017 DD - ISI Document Solution: 871IF AU - Yan JS AU - Cramer WA MA - yanjiush@bilbo.bio.purdue.edu, wac@bilbo.bio.purdue.edu RA - Yan JS TI - Molecular control of a bimodal distribution of quinone-analogue inhibitor binding sites in the cytochrome b(6)f complex SO - Journal of Molecular Biology. 344(2):481-493, 2004 Nov 19. AS - J. Mol. Biol 2004 Nov 19;344(2):481-493 PU - ACADEMIC PRESS LTD ELSEVIER SCIENCE LTD, 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND. URL: http://www.apnet.com IS - 0022-2836 MH - Quinone exchange cavity MH - Rieske iron-sulfur protein MH - Synechococcus sp pcc 7002 MH - Stigmatellin MH - Transporter. MH - Iron-sulfur protein MH - Bovine heart-mitochondria MH - Bc(1) complex MH - Escherichia-coli MH - Electron-transfer MH - Oxygenic photosynthesis MH - Crystal-structure MH - Ubiquinol oxidation MH - Structural basis MH - Bc complexes. AB - The 3.0-3.1 Angstrom X-ray structures of the cytochrome b(6)f complex from Mastigocladus laminosus and Chlamydomonas reinhardtii obtained in the presence of the p-side quinone-analogue inhibitor tridecyl-stigmatellin (TDS) are very similar. A difference occurs in the p-side binding position of TDS. In C. reinhardtii, TDS binds in the ring-in mode, as previously found for stigmatellin in X-ray structures of the cytochrome bc(1) complex. In this mode, the H-bonding chromone ring moiety of the TDS bound in the Q(p) niche is proximal to the ISP [2Fe-2S] cluster, and its 13 carbon tail extends through a portal to the large inter-monomer quinone-exchange cavity However, in M. laminosus, TDS binds in an oppositely oriented ring-out mode, with the tail inserted toward the Qp niche through the portal and the ring caught in the quinone-exchange cavity that is 20 A away from the [2Fe-2S] cluster. Site-directed mutagenesis of residues that might determine TDS binding was performed with the related transformable cyanobacterium Synechococcus sp. PCC 7002. The following changes in the sensitivity of electron transport activity to TDS and stigmatellin were observed: (a) little effect of mutation L193A in cytochrome b(6), which is proximal to the chromone of the ring-out TDS; (b) almost complete loss of sensitivity by mutation L111A in the ISP cluster binding region, which is close to the chromone of the ring-in TDS; (c) a ten and 60-fold increase associated with the mutation L81F in subunit W It was inferred that only the ring-in binding mode, in which the ring interacts with residues near the ISP, is inhibitory, and that residue 81 of subunit IV, which resides at the immediate entrance to the Qp niche, controls the relative binding affinity of inhibitor at the two different binding sites. (C) 2004 Elsevier Ltd. All rights reserved. [References: 50] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Molecular Biology & Genetics in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Yan JS Purdue Univ, Dept Biol Sci Lilly Hall Life Sci,915 W State St W Lafayette, IN 47907 USA Purdue Univ, Dept Biol Sci W Lafayette, IN 47907 USA <19> UI - 873BB-0008 DD - ISI Document Solution: 873BB AU - Bruno AK AU - Wetzel CM MA - cwetzel@email.smith.edu RA - Wetzel CM TI - The early light-inducible protein (ELIP) gene is expressed during the chloroplast-to-chromoplast transition in ripening tomato fruit SO - Journal of Experimental Botany. 55(408):2541-2548, 2004 Dec. AS - J. Exp. Bot 2004 Dec;55(408):2541-2548 PU - OXFORD UNIV PRESS, GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND. URL: http://www.oup.co.uk IS - 0022-0957 MH - Chloroplast MH - Chromoplast MH - Early light-inducible protein MH - Fruit ripening MH - Thylakoid. MH - A/b-binding-proteins MH - Photooxidative stress MH - Targeted proteins MH - Photosystem-ii MH - Pea MH - Nuclear MH - Arabidopsis MH - Barley MH - Biosynthesis MH - Plastids. AB - Chloroplast-to-chromoplast transitions during fruit ripening require massive transformation of the plastid internal membrane structure as the photosynthetic apparatus is disassembled. Early Light-Inducible Proteins (ELIPs) are known to accumulate in chloroplasts during thylakoid biogenesis and under stressful conditions. To determine if ELIP may also play a role in thylakoid disassembly during the chloroplast-to-chromoplast transition, ELIP mRNA expression was measured in tomato, Lycopersicon esculentum Mill. cv. Rutgers. An EST clone was identified in the Tomato Genome Project/Solanaceae Genomics Network database that has high sequence similarity with the amino acid sequence of Arabidopsis ELIP1 and ELIP2. It has complete identity in the two conserved regions of the protein. Genomic Southern blots indicate that the gene is a single copy in tomato. The genomic sequence shows the three-exon structure typical of ELIP sequences from other species. mRNA for this gene is barely detectable on northern blots from etiolated seedlings, but transiently accumulates to high levels 2 h after transfer to the light. Greenhouse-grown tomatoes were used to measure ELIP mRNA accumulation during fruit development and ripening. Tomato ELIP mRNA is detectable in all stages of fruit ripening, but is most abundant in the breaker/turning stage of development. A survey of tomato EST databases revealed that ELIP cDNA is also relatively abundant in developing flowers, which contain yellow chromoplasts. Combined, these results suggest that ELIP may play a newly-recognized role in the chloroplast-to-chromoplast transition process. [References: 56] LG - English PT - Article SB - Current Contents(R)/Agriculture, Biology & Environmental Sciences Current Contents(R)/Life Sciences CC - Plant Sciences in Current Contents(R)/Agricultural, Biology & Environmental Sciences. Animal & Plant Sciences in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Wetzel CM Smith Coll, Dept Biol Northampton, MA 01063 USA Smith Coll, Dept Biol Northampton, MA 01063 USA <20> UI - 873BB-0012 DD - ISI Document Solution: 873BB AU - Manter DK AU - Kerrigan J MA - dmanter@fs.fed.us RA - Manter DK TI - A/C-i curve analysis across a range of woody plant species: influence of regression analysis parameters and mesophyll conductance SO - Journal of Experimental Botany. 55(408):2581-2588, 2004 Dec. AS - J. Exp. Bot 2004 Dec;55(408):2581-2588 PU - OXFORD UNIV PRESS, GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND. URL: http://www.oup.co.uk IS - 0022-0957 MH - A/c-i curve analysis MH - Co2 assimilation MH - Mesophyll co2 conductance MH - Photosynthesis MH - Rubisco MH - Vcmax. MH - Co2 assimilation MH - C-3 plants MH - Photosynthesis MH - Leaves MH - Limitations MH - Rubisco MH - Diffusion MH - Nitrogen MH - Model MH - Exchange. AB - The analysis and interpretation of A/C-i curves (net CO2 assimilation rate, A, versus calculated substomatal CO2 concentration, C-i) is dependent upon a number of underlying assumptions. The influence of the C-i value at which the A/C-i curve switches between the Rubisco- and electron transport-limited portions of the curve was examined on A/C-i curve parameter estimates, as well as the effect of mesophyll CO2 conductance (g(m)) values on estimates of the maximum rate of Rubisco-mediated carboxylation (V-cmax). Based on an analysis using 19 woody species from the Pacific Northwest, significant variation occurred in the C-i value where the Rubisco- and electron transport-limited portions of the curve intersect (C-i_t), ranging from 20 Pa to 152 Pa and averaging c. 71 Pa and 37 Pa for conifer and broadleaf species, respectively. Significant effects on estimated A/C-i parameters (e.g. V-cmax) may arise when preliminary estimates of C-i_t, necessary for the multiple regression analyses, are set either too high or too low. However, when the appropriate threshold is used, a significant relationship between A/C-i and chlorophyll fluorescence estimates of carboxylation is achieved. The use of the V-cmax parameter to describe accurately the Rubisco activity from the A/C-i curve analysis is also dependent upon the assumption that C-i is approximately equal to chloroplast CO2 concentrations (C-c). If leaf mesophyll conductance is low, C-c will be much lower than C-i and will result in an underestimation of V-cmax from A/C-i curves. A large range of mesophyll conductance (g(m)) values was observed across the 19 species (0.005+/-0.002 to 0.189+/-0.011 mol m(-2) s(-1) for Tsuga heterophylla and Quercus garryana, respectively) and, on average, g(m) was 1.9 times lower for the conifer species (0.058+/-0.017 mol m(-2) s(-1) for conifers versus 0.112+/-0.020 mol m(-2) s(-1) for broadleaves). When this mesophyll limitation was accounted for in V-cmax estimates, considerable variation still existed between species, but the difference in V-cmax between conifer and broadleaf species was reduced from c. 11 mumol m(-2) s(-1) to 4 mumol m(-2) s(-1). For example, A/C-i curve estimates of V-cmax were 31.2+/-6.2 and 42.2+/-4.4 mumol m(-2) s(-1), and A/C-c curve estimates were 41.2+/-7.1 mumol m(-2) s(-1) and 45.0+/-4.8 mumol m(-2) s(-1), for the conifer and broadleaf species, respectively. [References: 24] LG - English PT - Article SB - Current Contents(R)/Agriculture, Biology & Environmental Sciences Current Contents(R)/Life Sciences CC - Plant Sciences in Current Contents(R)/Agricultural, Biology & Environmental Sciences. Animal & Plant Sciences in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Manter DK Forest Serv, USDA, PNW Res Stn 3200 Jefferson Way Corvallis, OR 97331 USA Forest Serv, USDA, PNW Res Stn Corvallis, OR 97331 USA Oregon State Univ, Dept Bot & Plant Pathol Corvallis, OR 97331 USA <21> UI - 871KJ-0001 DD - ISI Document Solution: 871KJ AU - Proctor MCF MA - M.C.F.Proctor@exeter.ac.uk RA - Proctor MCF TI - Light and desiccation responses of Weymouthia mollis and W-cochlearifolia, two pendulous rainforest epiphytes from Australia and New Zealand SO - Journal of Bryology. 26(Part 3):167-173, 2004. AS - J. Bryol 2004;26(Part 3):167-173 PU - MANEY PUBLISHING, HUDSON RD, LEEDS LS9 7DL, ENGLAND. URL: http://www.maney.co.uk IS - 0373-6687 MH - Mosses MH - Life-forms MH - Chlorophyll fluorescence MH - Carbon balance. MH - Water-relations MH - Chlorophyll fluorescence MH - Bryophytes MH - Patterns MH - Lichens. AB - The two species of Weymouthia occur in temperate rainforest in south-east Australia, New Zealand and southern Chile. Weymouthia cochlearifolia forms patches on trunks and branches, but can be pendulous under suitable conditions. Weymouthia mollis is typically of 'pendant' life-form, hanging from twigs and branches in the canopy. Photosynthetic electron flow in W. cochlearifolia reached 95% saturation at 160 mumol m(-2) s(-1) PPFD; corresponding figures for W. mollis ranged from 176 to 307 mumol m(-2) s(-1) PPFD or more. Both species tolerated 30 d desiccation at -41 MPa (74% r.h.) but survived lower humidities less well; W. mollis was the more desiccation tolerant of the two. The fluorescence parameter F-v/F-m recovered rapidly on re-wetting. It is suggested that the main desiderata for the pendant life-form are high and reasonably regular precipitation, some shelter from wind, and moderate (but not extreme) shade. These probably cannot be fully met around the year in deciduous forests at higher latitudes. [References: 29] LG - English PT - Article SB - Current Contents(R)/Agriculture, Biology & Environmental Sciences CC - Plant Sciences in Current Contents(R)/Agricultural, Biology & Environmental Sciences. EW - 2005 week 01 IN - Reprint available from: Proctor MCF Univ Exeter, Dept Biol Sci, Washington Singer Labs Perry Rd Exeter EX4 4QG Devon England Univ Exeter, Dept Biol Sci, Washington Singer Labs Exeter EX4 4QG Devon England <22> UI - 870ZP-0038 DD - ISI Document Solution: 870ZP AU - Motz C AU - Hornung T AU - Kersten M AU - McLachlin DT AU - Dunn SD AU - Wise JG AU - Vogel PD MA - pvogel@mail.smu.edu RA - Vogel PD TI - The subunit b dimer of the FoF1-ATP synthase interaction with F-1-ATPase as deduced by site-specific spin-labeling SO - Journal of Biological Chemistry. 279(47):49074-49081, 2004 Nov 19. AS - J. Biol. Chem 2004 Nov 19;279(47):49074-49081 PU - AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC, 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3996 USA. URL: http://www.asbmb.org IS - 0021-9258 MH - Coli atp synthase MH - Nucleotide-binding-sites MH - Escherichia-coli MH - 2nd stalk MH - Delta-subunit MH - Adenosine-triphosphatase MH - Resonance spectroscopy MH - F1f0-atp synthase MH - Dimerization domain MH - Crystal-structure. AB - We have used site-specific spin-labeling of single cysteine mutations within a water-soluble mutant of subunit b of the ATP synthase and employed electron spin resonance (ESR) spectroscopy to obtain information about the binding interactions of the b dimer with F-1-ATPase. Interaction of b(2) with a delta-depleted F-1 (F-1-delta) was also studied. The cysteine mutations used for spin-labeling were distributed throughout the cytosolic domain of the b subunit. In addition, each position between residues 101 and 114 of b was individually mutated to cysteine. All mutants were modified with a cysteine-reactive spin label. The room temperature ESR spectra of spin-labeled b(2) in the presence of F-1 or F-1-delta when compared with the spectra of free b(2) indicate a tight binding interaction between b(2) and F-1. The data suggest that b(2) packs tightly to F1 between residues 80 and the C terminus but that there are segments of b2 within that region where packing interactions are quite loose. Two-dimensional gel electrophoresis confirmed binding of the modified b mutants to F-1-ATPase as well as to F-1-delta. Subsequent addition of delta to F-1-delta.b(2) complex resulted in changes in the ESR spectra, indicating different binding interactions of b to F-1 in the presence or absence of delta. The data also suggest that the reconstitution of the ATP synthase is not ordered with respect to these subunits. Additional spectral components observed in b preparations that were spin-labeled between amino acid position 101 and 114 are indicative of either two populations of b subunits with different packing interactions or to helical bending within this region. [References: 66] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Biochemistry & Biophysics in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Vogel PD So Methodist Univ, Dept Biol Sci 6501 Airline Dr Dallas, TX 75275 USA So Methodist Univ, Dept Biol Sci Dallas, TX 75275 USA Univ Kaiserslautern, Fachbereich Chem D-67663 Kaiserslautern Germany Univ Western Ontario, Dept Biochem London ON N6A 5C1 Canada <23> UI - 870ZP-0056 DD - ISI Document Solution: 870ZP AU - Croce R AU - Morosinotto T AU - Ihalainen JA AU - Chojnicka A AU - Breton J AU - Dekker JP AU - van Grondelle R AU - Bassi R MA - croce@itc.it RA - Croce R TI - Origin of the 701-nm fluorescence emission of the Lhca2 subunit of higher plant photosystem I SO - Journal of Biological Chemistry. 279(47):48543-48549, 2004 Nov 19. AS - J. Biol. Chem 2004 Nov 19;279(47):48543-48549 PU - AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC, 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3996 USA. URL: http://www.asbmb.org IS - 0021-9258 MH - Light-harvesting complex MH - Chlorophyll-protein complexes MH - Crystal-structure MH - Mutation analysis MH - Pigment-binding MH - Antenna complex MH - Green plants MH - Reconstitution MH - Lhcii MH - Cp29. AB - Photosystem I of higher plants is characterized by red-shifted spectral forms deriving from chlorophyll chromophores. Each of the four Lhca1 to - 4 subunits exhibits a specific fluorescence emission spectrum, peaking at 688, 701, 725, and 733 nm, respectively. Recent analysis revealed the role of chlorophyll-chlorophyll interactions of the red forms in Lhca3 and Lhca4, whereas the basis for the fluorescence emission at 701 nm in Lhca2 is not yet clear. We report a detailed characterization of the Lhca2 subunit using molecular biology, biochemistry, and spectroscopy and show that the 701-nm emission form originates from a broad absorption band at 690 nm. Spectroscopy on recombinant mutant proteins assesses that this band represents the low energy form of an excitonic interaction involving two chlorophyll a molecules bound to sites A5 and B5, the same protein domains previously identified for Lhca3 and Lhca4. The resulting emission is, however, substantially shifted to higher energies. These results are discussed on the basis of the structural information that recently became available from x-ray crystallography (Ben Shem, A., Frolow, F., and Nelson, N. (2003) Nature 426, 630 - 635). We suggest that, within the Lhca subfamily, spectroscopic properties of chromophores are modulated by the strength of the excitonic coupling between the chromophores A5 and B5, thus yielding fluorescence emission spanning a large wavelength interval. It is concluded that the interchromophore distance rather than the transition energy of the individual chromophores or the orientation of transition vectors represents the critical factor in determining the excitonic coupling in Lhca pigment-protein complexes. [References: 31] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Biochemistry & Biophysics in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Croce R ITC, CNR, Ist Biofis Via Sommar 18 I-38100 Trento Italy ITC, CNR, Ist Biofis I-38100 Trento Italy Univ Verona, Dipartimento Sci & Tecnol I-37134 Verona Italy Univ Aix Marseille 2, LGBP, Fac Sci Luminy, Dept Biol F-13288 Marseille France Vrije Univ Amsterdam, Fac Sci, Div Phys & Astron NL-1081 HV Amsterdam Netherlands CEA, Serv Bioenerget F-91191 Gif Sur Yvette France <24> UI - 870ZP-0057 DD - ISI Document Solution: 870ZP AU - Komenda J AU - Reisinger V AU - Muller BC AU - Dobakova M AU - Granvogl B AU - Eichacker LA MA - eichacker@lmu.de RA - Eichacker LA TI - Accumulation of the D2 protein is a key regulatory step for assembly of the photosystem II reaction center complex in Synechocystis PCC 6803 SO - Journal of Biological Chemistry. 279(47):48620-48629, 2004 Nov 19. AS - J. Biol. Chem 2004 Nov 19;279(47):48620-48629 PU - AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC, 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3996 USA. URL: http://www.asbmb.org IS - 0021-9258 MH - Blue native electrophoresis MH - Encoded d1 protein MH - Membrane-protein MH - Chlamydomonas-reinhardtii MH - Arabidopsis-thaliana MH - Directed mutagenesis MH - Deletion mutagenesis MH - Thylakoid membranes MH - Electron-transport MH - Gene-product. AB - Accumulation of monomer and dimer photosystem (PS) II reaction center core complexes has been analyzed by two-dimensional Blue-native/ SDS-PAGE in Synechocystis PCC 6803 wild type and in mutant strains lacking genes psbA, psbB, psbC, psbDIC/DII, or the psbEFLJ operon. In vivo pulse-chase radiolabeling experiments revealed that mutant cells assembled PSII precomplexes only. In DeltapsbC and DeltapsbB, assembly of reaction center cores lacking CP43 and reaction center complexes was detected, respectively. In DeltapsbA, protein subunits CP43, CP47, D2, and cytochrome b(559) were synthesized, but proteins did not assemble. Similarly, in DeltapsbD/C lacking D2, and CP43, the de novo synthesized proteins D1, CP47, and cytochrome b559 did not form any mutual complexes, indicating that assembly of the reaction center complex is a prerequisite for assembly with core subunits CP47 and CP43. Finally, although CP43 and CP47 accumulated in DeltapsbEFLJ, D2 was neither expressed nor accumulated. We, furthermore, show that the amount of D2 is high in the strain lacking D1, whereas the amount of D1 is low in the strain lacking D2. We conclude that expression of the psbEFLJ operon is a prerequisite for D2 accumulation that is the key regulatory step for D1 accumulation and consecutive assembly of the PSII reaction center complex. [References: 60] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Biochemistry & Biophysics in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Eichacker LA Univ Munich, Inst Bot Menzinger Str 67 D-80368 Munich Germany Univ Munich, Inst Bot D-80368 Munich Germany Opatovicky Mlyn, Inst Microbiol Trebon 37981 Czech Republic Univ S Bohemia, Inst Phys Biol Nove Hrady 37005 Czech Republic Hoffmann La Roche AG, RCMG CH-4070 Basel Switzerland <25> UI - 870ZP-0060 DD - ISI Document Solution: 870ZP AU - Muller FL AU - Liu YH AU - Van Remmen H MA - mullerf@uthscsa.edu RA - Muller FL TI - Complex III releases superoxide to both sides of the inner mitochondrial membrane SO - Journal of Biological Chemistry. 279(47):49064-49073, 2004 Nov 19. AS - J. Biol. Chem 2004 Nov 19;279(47):49064-49073 PU - AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC, 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3996 USA. URL: http://www.asbmb.org IS - 0021-9258 MH - Cytochrome bc(1) complex MH - Hydrogen-peroxide production MH - Electron-transport chain MH - Respiratory-chain MH - Reactive oxygen MH - Q(o) site MH - Heart-mitochondria MH - Mutant mice MH - Ubihydroquinone oxidation MH - Chloroplast thylakoids. AB - Mechanisms of mitochondrial superoxide formation remain poorly understood despite considerable medical interest in oxidative stress. Superoxide is produced from both Complexes I and III of the electron transport chain, and once in its anionic form it is too strongly charged to readily cross the inner mitochondrial membrane. Thus, superoxide production exhibits a distinct membrane sidedness or "topology." In the present work, using measurements of hydrogen peroxide (Amplex red) as well as superoxide ( modified Cypridina luciferin analog and aconitase), we demonstrate that Complex I-dependent superoxide is exclusively released into the matrix and that no detectable levels escape from intact mitochondria. This finding fits well with the proposed site of electron leak at Complex I, namely the iron-sulfur clusters of the (matrix-protruding) hydrophilic arm. Our data on Complex III show direct extramitochondrial release of superoxide, but measurements of hydrogen peroxide production revealed that this could only account for similar to 50% of the total electron leak even in mitochondria lacking CuZn-superoxide dismutase. We posit that the remaining similar to 50% of the electron leak must be due to superoxide released to the matrix. Measurements of ( mitochondrial matrix) aconitase inhibition, performed in the presence of exogenous superoxide dismutase and catalase, confirmed this hypothesis. Our data indicate that Complex III can release superoxide to both sides of the inner mitochondrial membrane. The locus of superoxide production in Complex III, the ubiquinol oxidation site, is situated immediately next to the intermembrane space. This explains extramitochondrial release of superoxide but raises the question of how superoxide could reach the matrix. We discuss two models explaining this result. [References: 80] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Biochemistry & Biophysics in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Muller FL Univ Texas, Hlth Sci Ctr, Dept Cellular & Struct Biol 7703 Floyd Curl Dr,MSC 7762 San Antonio, TX 78229 USA Univ Texas, Hlth Sci Ctr, Dept Cellular & Struct Biol San Antonio, TX 78229 USA Univ Texas, Hlth Sci Ctr, Barshop Ctr Longev Studies San Antonio, TX 78229 USA S Texas Vet Hlth Care Syst, Dept Cellular & Struct Biol San Antonio, TX 78284 USA <26> UI - 870ZP-0067 DD - ISI Document Solution: 870ZP AU - Bhosale P AU - Larson AJ AU - Frederick JM AU - Southwick K AU - Thulin CD AU - Bernstein PS MA - paul.bernstein@hsc.utah.edu RA - Bernstein PS TI - Identification and characterization of a Pi isoform of glutathione S-transferase (GSTP1) as a zeaxanthin-binding protein in the macula of the human eye SO - Journal of Biological Chemistry. 279(47):49447-49454, 2004 Nov 19. AS - J. Biol. Chem 2004 Nov 19;279(47):49447-49454 PU - AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC, 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3996 USA. URL: http://www.asbmb.org IS - 0021-9258 MH - Human retina MH - Cytoplasmic membrane MH - In-vitro MH - Carotenoids MH - Isomerization MH - Degeneration MH - Xanthophylls MH - Pigment MH - Lutein MH - Liver. AB - Uptake, metabolism, and stabilization of xanthophyll carotenoids in the retina are thought to be mediated by specific xanthophyll-binding proteins (XBPs). A membrane-associated XBP was purified from human macula using ion-exchange chromatography followed by gel-exclusion chromatography. Two-dimensional gel electrophoresis showed a prominent spot of 23 kDa and an isoelectric point of 5.7. Using mass spectral sequencing methods and the public NCBI database, it was identified as a Pi isoform of human glutathione S-transferase (GSTP1). Dietary (3R,3'R)-zeaxanthin displayed the highest affinity with an apparent K-d of 0.33 muM, followed by (3R,3'S-meso)-zeaxanthin with an apparent K-d of 0.52 muM. (3R,3'R,6'R)-Lutein did not display any high-affinity binding to GSTP1. Other human recombinant glutathione S-transferase (GST) proteins, GSTA1 and GSTM1, exhibited only low affinity binding of xanthophylls. (3R,3'S-meso)-Zeaxanthin, an optically inactive non-dietary xanthophyll carotenoid present in the human macula, exhibited a strong induced CD spectrum in association with human macular XBP that was nearly identical to the CD spectrum induced by GSTP1. Likewise, dietary (3R,3'R)-zeaxanthin displayed alterations in its CD spectrum in association with GSTP1 and XBP. Other mammalian xanthophyll carrier proteins such as tubulin, high-density lipoprotein, low-density lipoprotein, albumin, and beta-lactoglobulin did not bind zeaxanthins with high affinity, and they failed to induce or alter xanthophyll CD spectra to any significant extent. Immunocytochemistry with an antibody to GSTP1 on human macula sections showed highest labeling in the outer and inner plexiform layers. These results indicate that GSTP1 is a specific XBP in human macula that interacts with (3R,3'S-meso)-zeaxanthin and dietary (3R,3'R)-zeaxanthin in contrast to apparently weaker interactions with (3R,3'R,6'R)-lutein. [References: 45] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Biochemistry & Biophysics in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Bernstein PS Univ Utah, Sch Med, Moran Eye Ctr, Dept Ophthalmol & Visual Sci 50 N Med Dr Salt Lake City, UT 84132 USA Univ Utah, Sch Med, Moran Eye Ctr, Dept Ophthalmol & Visual Sci Salt Lake City, UT 84132 USA Brigham Young Univ, Dept Chem & Biochem Provo, UT 84602 USA <27> UI - 872SU-0046 DD - ISI Document Solution: 872SU AU - Olmo-Mira MF AU - Gavira M AU - Richardson DJ AU - Castillo F AU - Moreno-Vivian C AU - Roldan MD MA - bb2rorum@uco.es RA - Roldan MD TI - NapF is a cytoplasmic iron-sulfur protein required for Fe-S cluster assembly in the periplasmic nitrate reductase SO - Journal of Biological Chemistry. 279(48):49727-49735, 2004 Nov 26. AS - J. Biol. Chem 2004 Nov 26;279(48):49727-49735 PU - AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC, 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3996 USA. URL: http://www.asbmb.org IS - 0021-9258 MH - Escherichia-coli k-12 MH - Sphaeroides dsm 158 MH - Rhodobacter-sphaeroides MH - Gene-expression MH - Rhodopseudomonas-capsulata MH - Polyacrylamide gels MH - Export pathway MH - Membrane MH - System MH - Sites. AB - The periplasmic nitrate reductase (Nap) is widespread in proteobacteria. NapA, the nitrate reductase catalytic subunit, contains a Mo-bisMGD cofactor and one [4Fe-4S] cluster. The nap gene clusters in many bacteria, including Rhodobacter sphaeroides DSM158, contain an napF gene, disruption of which drastically decreases both in vitro and in vivo nitrate reductase activities. In spite its importance in the Nap system, NapF has never been characterized biochemically, and its role remains unknown. The NapF protein has four polycysteine clusters that suggest that it is an iron-sulfur-containing protein. In the present study, a His(6)-tagged NapF protein was overproduced in Escherichia coli and purified anaerobically. The purified NapF protein was used to obtain polyclonal antibodies raised in rabbit, and cellular fractionation of R. sphaeroides followed by immunoprobing with anti-NapF antibodies revealed that the native NapF protein is located in the cytoplasm. This contrasts with the periplasmic location of the mature NapA. However, NapA could not be detected in an isogenic napF(-) strain of R. sphaeroides. The His(6)-tagged NapF protein displayed spectral properties indicative of Fe-S clusters, but these features were rapidly lost, suggesting cluster lability. However, reconstitution of the Fe-S centers into the apo-NapF protein was achieved in the presence of Azotobacter vinelandii cysteine desulfurase (NifS), and this allowed the recovery of nitrate reductase activity in NapA protein that had previously been treated with 2,2'-dipyridyl to remove the [4Fe-4S] cluster. This activity was not recovered in the absence of NapF. Taking into account the cytoplasmic localization of NapF, the presence of labile Fe-S clusters in the protein, the napF(-) strain phenotype, and the NapF-dependent reactivation of the 2,2'-dipyridyltreated NapA, we propose a role for NapF in assembling the [4Fe-4S] center of the catalytic subunit NapA. [References: 44] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Biochemistry & Biophysics in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Roldan MD Univ Cordoba, Dept Bioquim & Biol Mol, Edificio Severo Ochoa Campus Rabanales,1a Planta E-14071 Cordoba Spain Univ Cordoba, Dept Bioquim & Biol Mol, Edificio Severo Ochoa E-14071 Cordoba Spain Univ E Anglia, Sch Biol Sci Norwich NR4 7TJ Norfolk England <28> UI - 872SU-0056 DD - ISI Document Solution: 872SU AU - Loschi L AU - Brokx SJ AU - Hills TL AU - Zhang G AU - Bertero MG AU - Lovering AL AU - Weiner JH AU - Strynadka NCJ MA - natalie@byron.biochem.ubc.ca RA - Strynadka NCJ TI - Structural and biochemical identification of a novel bacterial oxidoreductase SO - Journal of Biological Chemistry. 279(48):50391-50400, 2004 Nov 26. AS - J. Biol. Chem 2004 Nov 26;279(48):50391-50400 PU - AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC, 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3996 USA. URL: http://www.asbmb.org IS - 0021-9258 MH - Dimethyl-sulfoxide reductase MH - Human sulfite oxidase MH - Crystal-structure MH - Escherichia-coli MH - Aldehyde oxidoreductase MH - Xanthine dehydrogenase MH - Rhodobacter-capsulatus MH - Angstrom resolution MH - Nitrate reductase MH - Electron-transfer. AB - By using a bioinformatics screen of the Escherichia coli genome for potential molybdenum-containing enzymes, we have identified a novel oxidoreductase conserved in the majority of Gram-negative bacteria. The identified operon encodes for a proposed heterodimer, YedYZ in Escherichia coli, consisting of a soluble catalytic subunit termed YedY, which is likely anchored to the membrane by a heme-containing trans-membrane subunit termed YedZ. YedY is uniquely characterized by the presence of one molybdenum molybdopterin not conjugated by an additional nucleotide, and it represents the only molybdoenzyme isolated from E. coli characterized by the presence of this cofactor form. We have further characterized the catalytic subunit YedY in both the molybdenum- and tungsten-substituted forms by using crystallographic analysis. YedY is very distinct in overall architecture from all known bacterial reductases but does show some similarity with the catalytic domain of the eukaryotic chicken liver sulfite oxidase. However, the strictly conserved residues involved in the metal coordination sphere and in the substrate binding pocket of YedY are strikingly different from that of chicken liver sulfite oxidase, suggesting a catalytic activity more in keeping with a reductase than that of a sulfite oxidase. Preliminary kinetic analysis of YedY with a variety of substrates supports our proposal that YedY and its many orthologues may represent a new type of membrane-associated bacterial reductase. [References: 51] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Biochemistry & Biophysics in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Strynadka NCJ Univ British Columbia, Dept Biochem & Mol Biol 2146 Hlth Sci Mall Vancouver BC V6T 1Z3 Canada Univ British Columbia, Dept Biochem Vancouver BC V6T 1Z3 Canada Univ Alberta, Dept Biochem, Canadian Inst Hlth Res Membrane Prot Res Grp Edmonton AB T6G 2H7 Canada <29> UI - 872SU-0071 DD - ISI Document Solution: 872SU AU - Barros MH AU - Bandy B AU - Tahara EB AU - Kowaltowski AJ MA - alicia@iq.usp.br RA - Kowaltowski AJ TI - Higher respiratory activity decreases mitochondrial reactive oxygen release and increases life span in Saccharomyces cerevisiae SO - Journal of Biological Chemistry. 279(48):49883-49888, 2004 Nov 26. AS - J. Biol. Chem 2004 Nov 26;279(48):49883-49888 PU - AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC, 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3996 USA. URL: http://www.asbmb.org IS - 0021-9258 MH - Calorie restriction MH - Oxidative stress MH - Species production MH - Stationary-phase MH - Dna-damage MH - Short-term MH - Yeast MH - Longevity MH - Superoxide MH - Generation. AB - Increased replicative longevity in Saccharomyces cerevisiae because of calorie restriction has been linked to enhanced mitochondrial respiratory activity. Here we have further investigated how mitochondrial respiration affects yeast life span. We found that calorie restriction by growth in low glucose increased respiration but decreased mitochondrial reactive oxygen species production relative to oxygen consumption. Calorie restriction also enhanced chronological life span. The beneficial effects of calorie restriction on mitochondrial respiration, reactive oxygen species release, and replicative and chronological life span could be mimicked by uncoupling agents such as dinitrophenol. Conversely, chronological life span decreased in cells treated with antimycin (which strongly increases mitochondrial reactive oxygen species generation) or in yeast mutants null for mitochondrial superoxide dismutase (which removes superoxide radicals) and for RTG2 (which participates in retrograde feedback signaling between mitochondria and the nucleus). These results suggest that yeast aging is linked to changes in mitochondrial metabolism and oxidative stress and that mild mitochondrial uncoupling can increase both chronological and replicative life span. [References: 40] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Biochemistry & Biophysics in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Kowaltowski AJ Av Prof Lineu Prestes 748,Cidade Univ BR-05508900 Sao Paulo Brazil Univ Estadual Paulista, Inst Biociencias Botucatu, Dept Genet BR-18618000 Sao Paulo Brazil Univ Saskatchewan, Coll Pharm & Nutr Saskatoon SK S7N 5C9 Canada Univ Sao Paulo, Inst Quim, Dept Bioquim BR-05508900 Sao Paulo Brazil <30> UI - 872SU-0072 DD - ISI Document Solution: 872SU AU - Schonfeld C AU - Wobbe L AU - Borgstadt R AU - Kienast A AU - Nixon PJ AU - Kruse O MA - olaf.kruse@uni-bielefeld.de RA - Kruse O TI - The nucleus-encoded protein MOC1 is essential for mitochondrial light acclimation in Chlamydomonas reinhardtii SO - Journal of Biological Chemistry. 279(48):50366-50374, 2004 Nov 26. AS - J. Biol. Chem 2004 Nov 26;279(48):50366-50374 PU - AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC, 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3996 USA. URL: http://www.asbmb.org IS - 0021-9258 MH - Transcription termination factor MH - Dominant selectable marker MH - State transitions MH - Alternative oxidase MH - Plant-mitochondria MH - Electron-transfer MH - Gene-expression MH - Photosystem-i MH - Complex-i MH - Dna. AB - Mitochondrial respiration plays an important role in optimizing photosynthetic efficiency in plants. As yet, the mechanisms by which plant mitochondria sense and respond to changes in the environment are unclear, particularly when exposed to light. Here we describe the characterization of the Chlamydomonas reinhardtii mutant stm6, which was identified on the basis of impaired state transitions, a mechanism that regulates light harvesting in the chloroplast. The gene disrupted in stm6, termed Moc1, encodes a homologue of the human mitochondrial transcription termination factor (mTERF). MOC1 is targeted to the mitochondrion, and its expression is up-regulated in response to light. Loss of MOC1 causes a high light-sensitive phenotype and disrupts the transcription and expression profiles of the mitochondrial respiratory complexes causing, as compared with wild type, light-mediated changes in the expression levels of nuclear and mitochondrial encoded cytochrome c oxidase subunits and ubiquinone-NAD subunits. The absence of MOC1 leads to a reduction in the levels of cytochrome c oxidase and of rotenone-insensitive external NADPH dehydrogenase activities of the mitochondrial respiratory electron transfer chain. Overall, we have identified a novel mitochondrial factor that regulates the composition of the mitochondrial respiratory chain in the light so that it can act as an effective sink for reductant produced by the chloroplast. [References: 66] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Biochemistry & Biophysics in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Kruse O Univ Bielefeld, Mol Cell Physiol Grp, Dept Biol D-33501 Bielefeld Germany Univ Bielefeld, Mol Cell Physiol Grp, Dept Biol D-33501 Bielefeld Germany Univ London Imperial Coll Sci Technol & Med, Dept Biol Sci London SW7 2AZ England <31> UI - 872SU-0073 DD - ISI Document Solution: 872SU AU - Armstrong JS AU - Yang HY AU - Duan W AU - Whiteman M MA - bchjsa@nus.edu.sg RA - Armstrong JS TI - Cytochrome bc(1) regulates the mitochondrial permeability transition by two distinct pathways SO - Journal of Biological Chemistry. 279(48):50420-50428, 2004 Nov 26. AS - J. Biol. Chem 2004 Nov 26;279(48):50420-50428 PU - AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC, 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3996 USA. URL: http://www.asbmb.org IS - 0021-9258 MH - Adenine-nucleotide translocase MH - Iron-sulfur protein MH - Respiratory-chain MH - Cell-death MH - Cyclophilin-d MH - Electron-transfer MH - Complex-iii MH - Superoxide-production MH - Hydrogen-peroxide MH - Bc1 complex. AB - The mitochondrial permeability transition (MPT) pore is a calcium-sensitive channel in the mitochondrial inner membrane that plays a crucial role in cell death. Here we show that cytochrome bc(1) regulates the MPT in isolated rat liver mitochondria and in CEM and HL60 cells by two independent pathways. Glutathione depletion activated the MPT via increased production of reactive oxygen species (ROS) generated by cytochrome bc1. The ROS producing mechanism in cytochrome bc1 involves movement of the "Rieske" iron-sulfur protein subunit of the enzyme complex, because inhibition of cytochrome bc1 by pharmacologically blocking iron-sulfur protein movement completely abolished ROS production, MPT activation, and cell death. The classical inhibitor of the MPT, cyclosporine A, had no protective effect against MPT activation. In contrast, the calcium-activated, cyclosporine A-regulated MPT in rat liver mitochondria was also blocked with inhibitors of cytochrome bc1. These results indicate that electron flux through cytochrome bc1 regulates two distinct pathways to the MPT, one unregulated and involving mitochondrial ROS and the other regulated and activated by calcium. [References: 55] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Biochemistry & Biophysics in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Armstrong JS Natl Univ Singapore, Dept Biochem Kent Rd Singapore 117597 Singapore Natl Univ Singapore, Dept Biochem Singapore 117597 Singapore <32> UI - 873GZ-0040 DD - ISI Document Solution: 873GZ AU - Hillenkamp J AU - Hussain AA AU - Jackson TL AU - Cunningham JR AU - Marshall J MA - hillenka@hotmail.com RA - Hillenkamp J TI - Taurine uptake by human retinal pigment epithelium: Implications for the transport of small solutes between the choroid and the outer retina SO - Investigative Ophthalmology & Visual Science. 45(12):4529-4534, 2004 Dec. AS - Invest. Ophthalmol. Vis. Sci 2004 Dec;45(12):4529-4534 PU - ASSOC RESEARCH VISION OPHTHALMOLOGY INC, 12300 TWINBROOK PARKWAY, ROCKVILLE, MD 20852-1606 USA IS - 0146-0404 MH - Bruchs membrane MH - Cell line MH - Age MH - Expression MH - Plasma. AB - PURPOSE. To characterize the Michaelis-Menten kinetics of the taurine transporter ( TT) in retinal pigment epithelium (RPE) freshly isolated from human donor eyes. To identify the rate limiting compartment in the pathway of taurine delivery from the choroidal blood supply to the outer retina composed by Bruch's-choroid ( BC) and the RPE in the human older age group. METHODS. In human donor samples (4 melanoma-affected eyes, and 14 control eyes; age range, 62-93 years), radiochemical techniques were used to determine the RPE taurine accumulation at various exogenous concentrations. The transport capability of human RPE was obtained from a kinetic analysis of the high-affinity carrier over a substrate concentration of 1 to 60 muM taurine. RESULTS. Uptake of taurine into human RPE at a taurine concentration of 1 muM was independent of donor age (P > 0.05) and averaged at 2.83 +/- 0.27 (SEM) pmol/10 minutes per 6-mm trephine. Taurine transport by human RPE was mediated by a high-affinity carrier of K-m 50 muM and V-max of 267 pmol/10 minutes per 5-mm disc. CONCLUSIONS. In human donor RPE, uptake of taurine remained viable in the age range 62 to 93 years. Taurine transport rates in the RPE were lower than across the isolated BC complex, and thus the data suggest that the former compartment houses the rate-limiting step in the delivery of taurine to the outer retina. [References: 29] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Medical Research, Organs & Systems in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Hillenkamp J St Thomas Hosp, Rayne Inst, Dept Ophthalmol Lambeth Palace Rd London SE1 7EH England St Thomas Hosp, Rayne Inst, Dept Ophthalmol London SE1 7EH England St Thomas Hosp, Rayne Inst, Dept Pharmacol London SE1 7EH England <33> UI - 873FC-0017 DD - ISI Document Solution: 873FC AU - Sugishima M AU - Migita CT AU - Zhang XH AU - Yoshida T AU - Fukuyama K MA - fukuyama@bio.sci.osaka-u.ac.jp RA - Fukuyama K TI - Crystal structure of heme oxygenase-1 from cyanobacterium Synechocystis sp PCC 6803 in complex with heme SO - European Journal of Biochemistry. 271(22):4517-4525, 2004 Nov. AS - Eur. J. Biochem 2004 Nov;271(22):4517-4525 PU - BLACKWELL PUBLISHING LTD, 9600 GARSINGTON RD, OXFORD OX4 2DG, OXON, ENGLAND. URL: http://www.blackwell-science.com IS - 0014-2956 MH - Crystal structure MH - Cyanobacterium MH - Heme oxygenase MH - Light-harvesting pigment. MH - Cyanidium-caldarium MH - Rat heme MH - Corynebacterium-diphtheriae MH - Phytochrome-chromophore MH - Phytobilin biosynthesis MH - Pcc 6803 MH - Ferredoxin MH - Mechanism MH - Product MH - Program. AB - Heme oxygenase (HO) catalyzes the oxidative degradation of heme utilizing molecular oxygen and reducing equivalents. In photosynthetic organisms, HO functions in the biosynthesis of such open-chain tetrapyrroles as phyto-chromobilin and phycobilins, which are involved in the signal transduction for light responses and light harvesting for photosynthesis, respectively. We have determined the first crystal structure of a HO-1 from a photosynthetic organism, Synechocystis sp. PCC 6803 (Syn HO-1), in complex with heme at 2.5 Angstrom resolution. Heme-Syn HO-1 shares a common folding with other heme-HOs. Although the heme pocket of heme-Syn HO-1 is, for the most part, similar to that of mammalian HO-1, they differ in such features as the flexibility of the distal helix and hydrophobicity. In addition, 2-propanol derived from the crystallization solution occupied the hydrophobic cavity, which is proposed to be a CO trapping site in rat HO-1 that suppresses product inhibition. Although Syn HO-1 and mammalian HO-1 are similar in overall structure and amino acid sequence (57% similarity vs. human HO-1), their molecular surfaces differ in charge distribution. The surfaces of the heme binding sides are both positively charged, but this patch of Syn HO-1 is narrow compared to that of mammalian HO-1. This feature is suited to the selective binding of ferredoxin, the physiological redox partner of Syn HO-1; the molecular size of ferredoxin is approximate to 10 kDa whereas the size of NADPH-cytochrome P450 reductase, a reducing partner of mammalian HO-1, is approximate to 77 kDa. A docking model of heme-Syn HO-1 and ferredoxin suggests indirect electron transfer from an iron-sulfur cluster in ferredoxin to the heme iron of heme-Syn HO-1. [References: 51] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Biochemistry & Biophysics in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Fukuyama K Osaka Univ, Grad Sch Sci, Dept Biol Osaka 5600043 Japan Osaka Univ, Grad Sch Sci, Dept Biol Osaka 5600043 Japan Yamaguchi Univ, Fac Agr, Dept Biol Chem Yamaguchi 753 Japan Yamagata Univ, Sch Med, Dept Biochem Yamagata 99023 Japan <34> UI - 869EH-0004 DD - ISI Document Solution: 869EH AU - Ditmarova L AU - Kmet J AU - Strelcova K AU - Gomory D MA - ditmarova@sav.savzv.sk, kmet@vsld.tuzvo.sk, strelcov@vsld.tuzvo.sk, gomory@vsld.tuzvo.sk RA - Ditmarova L TI - Effects of temperature on selected physiological parameters of young beech trees under stress conditions SO - Ekologia-Bratislava. 23(2):152-161, 2004. AS - Ekol. Bratisl 2004;23(2):152-161 PU - SLOVAK ACADEMIC PRESS LTD, PO BOX 57 NAM SLOBODY 6, 810 05 BRATISLAVA, SLOVAKIA. URL: http://www.europe.idealibrary.com/ IS - 1335-342X MH - Stress physiology MH - Chlorophyll fluorescence MH - Chlorophylls MH - Temperature stress MH - Fagus sylvatica l. MH - Fagus-sylvatica MH - Impact MH - Leaves. AB - We assessed physiological characteristics (chlorophyll a fluorescence, photosynthetic pigments) of shade leaves of the beech (Fagus sylvatica L.) in (measured 1, 2, 3, 7 and 14 days before the leaf sampling). The study was performed in two locations under different pollution load. The leaf characteristics were observed on 15 year old trees from the understorey. We identified a significant negative influence of the temperature difference related to the long term average (25 years) on the basic fluorescence (F-0) and a positive influence of deviation of maximum temperatures from the long term average on the ratio of the variable to maximum fluorescence (F/F-m). These trends were observed for short time periods (1-3 days) and they were mainly true for parameters measured on upper (adaxial) side of assimilatory organs of trees at both localities. In the photosynthetic pigments it is significant influence of the deviation of maximum temperatures measured one day before the leaf sampling on the pigment content values (mg.dm(-2)) at both localities. [References: 14] LG - English PT - Article SB - Current Contents(R)/Agriculture, Biology & Environmental Sciences CC - Environment/Ecology in Current Contents(R)/Agricultural, Biology & Environmental Sciences. EW - 2005 week 01 IN - Reprint available from: Ditmarova L Slovak Acad Sci, Inst Forest Ecol Sturova 2 Zvolen Slovakia Slovak Acad Sci, Inst Forest Ecol Zvolen Slovakia <35> UI - 869MF-0002 DD - ISI Document Solution: 869MF AU - Weinglass AB AU - Whitelegge JP AU - Kaback HR MA - adamw@hhmi.ucla.edu RA - Weinglass AB TI - Integrating mass spectrometry into membrane protein drug discovery [Review] SO - Current Opinion in Drug Discovery & Development. 7(5):589-599, 2004 Sep. AS - Curr. Opin. Drug Discov. Dev 2004 Sep;7(5):589-599 PU - THOMSON SCIENTIFIC, 34-42 CLEVELAND STREET, LONDON, W1T 4JE, ENGLAND IS - 1367-6733 MH - Disease MH - Mass spectrometry MH - Mechanism MH - Membrane protein MH - Proteomics MH - Screening. MH - Hereditary ceroid-lipofuscinosis MH - Mitochondrial atp synthase MH - 2-dimensional gel-electrophoresis MH - Total chemical-synthesis MH - Escherichia-coli MH - Electrospray-ionization MH - Proteomic analysis MH - Potassium channel MH - K+-channel MH - Subunit-c. AB - Membrane proteins represent a valuable source of potential drug targets due to their intimate involvement in a wide variety of disease states, including diabetes, cancer and neurological disorders. Defining the proteome of these often rare amphipathic molecules can be accomplished by exploiting the highly accurate and sensitive nature of mass spectrometry (MS). Technical advances have enabled MS to become a valuable tool for detailed mechanistic investigations into membrane proteins of unknown and known structure. The transfer of MS-screening strategies that have already been successfully used to identify interactions between soluble proteins and potential ligands, should allow the identification of drug candidates for membrane proteins in the near future. [References: 84] LG - English PT - Review SB - Current Contents(R)/Life Sciences CC - Pharmacology & Toxicology in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Weinglass AB Univ Calif Los Angeles, Howard Hughes Med Inst, Dept Physiol, Inst Mol Biol Los Angeles, CA 90095 USA Univ Calif Los Angeles, Howard Hughes Med Inst, Dept Physiol, Inst Mol Biol Los Angeles, CA 90095 USA Univ Calif Los Angeles, Howard Hughes Med Inst, Dept Microbiol & Mol Genet, Inst Mol Biol Los Angeles, CA 90095 USA Univ Calif Los Angeles, Pasarow Mass Spectrometry Lab, Dept Psychiat & Behav Sci, Inst Neuropsychiat Los Angeles, CA 90095 USA Univ Calif Los Angeles, Dept Chem & Biochem Los Angeles, CA 90095 USA <36> UI - 872CG-0009 DD - ISI Document Solution: 872CG AU - Chen ZQ AU - Li Y AU - Pan JM MA - zchen@seas.marine.usf.edu RA - Chen ZQ TI - Distributions of colored dissolved organic matter and dissolved organic carbon in the Pearl River Estuary, China SO - Continental Shelf Research. 24(16):1845-1856, 2004 Oct. AS - Cont. Shelf Res 2004 Oct;24(16):1845-1856 PU - PERGAMON-ELSEVIER SCIENCE LTD, THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND. URL: http://www.elsevier.com IS - 0278-4343 MH - Cdom MH - Doc MH - Optical properties MH - Pearl river estuary MH - Remote sensing. MH - Southern baltic sea MH - Optical-properties MH - Orinoco river MH - Fluorescence properties MH - Yellow substance MH - Absorption MH - Waters MH - Cdom MH - Spectroscopy MH - Chlorophyll. AB - The distributions of colored dissolved organic matter (CDOM) and of dissolved organic carbon (DOC) were studied in the Pearl River Estuary from 18 to 26 July 1999 (during the wet season). The highest level of CDOM was found in the fresh water, and lowest in the sea water, indicating the river water is a main source of CDOM in this estuary and may has impact on the optical properties of the South China Sea. However, the CDOM concentration is relatively low compared to the reports from other estuaries in the world. CDOM also did not show a conservative mixing behavior in the Pearl River Estuary. This non-conservative behavior may not be due to removal processes (such as flocculation and photodegradation), but is probably the result of different water mass sources having distinct CDOM composition and optical properties. DOC concentration, contrary to CDOM, varied little with the salinity gradient, leading to a different distribution between CDOM and DOC in the Pearl River Estuary. The absence of a co-variation between CODM with DOC suggests that the contribution of CDOM to DOC is variable and it is probably not feasible to estimate DOC by the remote sensing of CDOM in the Pearl River Estuary. (C) 2004 Elsevier Ltd. All rights reserved. [References: 32] LG - English PT - Article SB - Current Contents(R)/Agriculture, Biology & Environmental Sciences CC - Aquatic Sciences in Current Contents(R)/Agricultural, Biology & Environmental Sciences. EW - 2005 week 01 IN - Reprint available from: Chen ZQ Univ S Florida, Coll Marine Sci 140 7th Ave S St Petersburg, FL 33701 USA Inst Oceanog 2 Hangzhou 310012 Peoples R China Hong Kong Univ Sci & Technol, CCAR Kowloon Hong Kong Peoples R China <37> UI - 872CG-0016 DD - ISI Document Solution: 872CG AU - Tan YH AU - Huang LM AU - Chen QC AU - Huang XP MA - tanyh@sesio.ac.cn RA - Tan YH TI - Seasonal variation in zooplankton composition and grazing impact on phytoplankton standing stock in the Pearl River Estuary, China SO - Continental Shelf Research. 24(16):1949-1968, 2004 Oct. AS - Cont. Shelf Res 2004 Oct;24(16):1949-1968 PU - PERGAMON-ELSEVIER SCIENCE LTD, THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND. URL: http://www.elsevier.com IS - 0278-4343 MH - Mesozooplankton MH - Copepods MH - Grazing MH - Pearl river estuary MH - Gut fluorescence. MH - Copepod temora-longicornis MH - Vertical migration MH - Trophic gradients MH - Swimming activity MH - Arctic copepods MH - Gironde estuary MH - Ingestion rates MH - Coastal waters MH - Size structure MH - Gut clearance. AB - The composition, abundance, distribution and grazing impact of dominant components of the meso- and macrozooplankton community were investigated in the Pearl River Estuary (PRE) wet and dry season cruises during the summer of 1999 and winter 2000, respectively. Throughout the investigation, mesozooplankton, comprised mainly of copepods, dominated numerically and by species richness, accounting for at least 73% of the total mesozooplankton in the PRE. The copepods Acartia spinicauda, Pavocalauus crassirostris, Oithona rigida, Paracalanus aculeatus and Euterpina acutifrons, numerically dominated zooplankton counts, while during the dry season the zooplankton community was dominated by the copepods Paracalanus serrulus, Pauocalanus crassirostris, Paracalanus paruus, Acartia spinicauda and Oithona spp. The average evacuation rates of the copepods were 0.032 +/- 0.006 and 0.039 +/- 0.008 min(-1) for winter and summer, respectively. The grazing impact of the most abundant zooplankton taxa accounted for up to 85% of all zooplankton counted at each station. The grazing impact of zooplankton, especially copepods, changed seasonally and spatially, varying between <0.3% and 75% of the chlorophyll standing stock, or up to 104% of the daily phytoplankton production in summer and 21% in winter. (C) 2004 Elsevier Ltd. All rights reserved. [References: 60] LG - English PT - Article SB - Current Contents(R)/Agriculture, Biology & Environmental Sciences CC - Aquatic Sciences in Current Contents(R)/Agricultural, Biology & Environmental Sciences. EW - 2005 week 01 IN - Reprint available from: Tan YH Chinese Acad Sci, S China Sea Oceanog Inst Guangzhou Peoples R China Chinese Acad Sci, S China Sea Oceanog Inst Guangzhou Peoples R China <38> UI - 870JM-0006 DD - ISI Document Solution: 870JM AU - Pena-Castro JM AU - Martinez-Jeronimo F AU - Esparza-Garcia F AU - Canizares-Villanueva RO MA - rcanizar@mail.cinvestav.mx RA - Canizares-Villanueva RO TI - Phenotypic plasticity in Scenedesmus incrassatulus (Chlorophyceae) in response to heavy metals stress SO - Chemosphere. 57(11):1629-1636, 2004 Dec. AS - Chemosphere 2004 Dec;57(11):1629-1636 PU - PERGAMON-ELSEVIER SCIENCE LTD, THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND. URL: http://www.elsevier.com IS - 0045-6535 MH - Scenedesmus incrassatulus MH - Cadmium MH - Copper MH - Chromium(vi) MH - Morphotypes. MH - Colony formation MH - Alga scenedesmus MH - Chromium MH - Toxicity MH - Cultures MH - Copper MH - Acutus MH - Phytoplankton MH - Pond. AB - The microalgae genus Scenedesmus is commonly found in freshwater bodies, wastewater facilities and water polluted with heavy metals. Phenotypic plasticity in Scenedesmus has been documented in response to a wide variety of conditions, however, heavy metals have not been comprehensively documented as phenotypic plasticity inducers. In this study, we report the phenotypic plasticity of Scenedesmus incrassatulus (a non-spiny, four-cell coenobium forming species) in response to EC50 value of copper, cadmium and hexavalent chromium. S. incrassatulus was grown in batch cultures in the presence of each metal. Chlorophyll-a content, cell size, parameters derived from the schematic energy-flux model for photosystem II, and morphotype expressions were recorded. Divalent cation metals induced unicellular forms, and hexavalent chromium produced out-of-shape coenobia corresponding to various stages of autospore formation. The changes induced by divalent metals were interpreted as phenotypic plasticity, because they were always associated to population doublings and were reversible when toxicant pressure was removed (only for Cu). Copper was the best inductor of unicellular forms and also affected significantly all the photosynthetic parameters measured. The developed morphotypes could confer ecological advantages to S. incrassatulus in metal stressed environments. (C) 2004 Elsevier Ltd. All rights reserved. [References: 27] LG - English PT - Article SB - Current Contents(R)/Agriculture, Biology & Environmental Sciences CC - Environment/Ecology in Current Contents(R)/Agricultural, Biology & Environmental Sciences. EW - 2005 week 01 IN - Reprint available from: Canizares-Villanueva RO Ctr Invest Estudios Avanzados, Inst Politecn Nacl, Dept Biotecnol & Bioingn, Lab Biotecnol Microalgas Ave IPN 2508,San Pedro Azatenco Mexico City 07360 DF Mexico Ctr Invest Estudios Avanzados, Inst Politecn Nacl, Dept Biotecnol & Bioingn, Lab Biotecnol Microalgas Mexico City 07360 DF Mexico Ctr Invest Estudios Avanzados, Inst Politecn Nacl, Dept Biotecnol & Bioingn, Lab Ecol Microbiana Mexico City 07360 DF Mexico Escuela Nacl Ciencias Biol, Inst Politecn Nacl, Lab Hidrol Expt Mexico City 07360 DF Mexico <39> UI - 870EP-0004 DD - ISI Document Solution: 870EP AU - Shivaji S AU - Reddy GSN AU - Aduri RP AU - Kutty R AU - Ravenschlag K MA - shivas@ccmb.res.in RA - Shivaji S TI - Bacterial diversity of a soil sample from Schirmacher Oasis, Antarctica SO - Cellular & Molecular Biology. 50(5):525-536, 2004 Jul. AS - Cell. Mol. Biol 2004 Jul;50(5):525-536 PU - CELLULAR & MOLECULAR BIOLOGY, PROF R WEGMANN RESIDENCE HAUSSMANN 1 AVENUE DU PAVE NEUF, 93160 NOISY-LE-GRAND, FRANCE IS - 0145-5680 MH - 16s rrna gene MH - Clones diversity MH - Antarctica MH - Psychrophiles. MH - 16s ribosomal-rna MH - Cyanobacterial mat sample MH - Mcmurdo dry valleys MH - Sp-nov. MH - Psychrophilic bacterium MH - Microbial diversity MH - Community structure MH - Gene cloning MH - Rapid method MH - Lake vostok. AB - The bacterial diversity of a soil sample collected in the vicinity of Lake Zub, Schirmacher Oasis, Antarctica, was determined both by establishing pure colonies of culturable bacteria and by cloning the total 16S rDNA of the soil and establishing the phylogeny of the clones. Analysis of the 16S rRNA gene clones indicated that the bacteria belonged to the classes alpha-proteobacteria, beta-proteobacteria, gamma-proteobacteria, Gemmatimonas, Bacteriodetes, Actinobacteria, Chloroflexi and Chlamydiae. In addition, seven clones were categorized as unidentified and unculturable in the classes of beta-Proteobacteria, Actinobacteria, Chloroflexi and Chlamydiae. Further, the culturable bacteria from the same site were identified as belonging to the genera. Pseudomonas, Sphingobacterium, Arthrobacter, Micrococcus, Brevondimonas, Rhodococcus and Microbacterium. These results identify for the first time the presence of bacteria belonging to the genera Brevundimonas, Microbacterium, Rhodococcus, Serratia, Enterobacter, Rhodopseudomonas, Sphingomonas, Acidovorax, Burkholderia, Nevskia, Gemmatimonas, Xanthomonas and Flexibacter in Antarctica. Further, comparison of the Antarctic soil bacterial diversity with other cold habitats of Antarctica like from sediments, ice and cyanobacterial mat samples indicated that the bacterial diversity in soil was similar to the diversity observed in the continental shelf sediment sample. The Antarctic soil clones also resembled the bacterial diversity of soils from other geographical regions, but were unique in that none of the clones from the soil belonged to the uncultured Y, O, G, A and B groups (24) common to all soil samples. [References: 69] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Cell & Developmental Biology in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Shivaji S Ctr Cellular & Mol Biol Uppal Rd Hyderabad 500007 Andhra Pradesh India Ctr Cellular & Mol Biol Hyderabad 500007 Andhra Pradesh India Max Planck Inst Marine Microbiol D-28359 Bremen Germany <40> UI - 870QM-0014 DD - ISI Document Solution: 870QM AU - Yuan JM AU - Ross RK AU - Gao YT AU - Qu YH AU - Chu XD AU - Yu MC MA - jyuan@usc.edu RA - Yuan JM TI - Prediagnostic levels of serum micronutrients in relation to risk of gastric cancer in Shanghai, China SO - Cancer Epidemiology, Biomarkers & Prevention. 13(11 Part 1):1772-1780, 2004 Nov. AS - Cancer Epidemiol. Biomarkers Prev 2004 Nov;13(11 Part 1):1772-1780 PU - AMER ASSOC CANCER RESEARCH, 615 CHESTNUT ST, 17TH FLOOR, PHILADELPHIA, PA 19106-4404 USA. URL: http://www.aacr.org IS - 1055-9965 MH - Beta-carotene MH - Subsequent risk MH - Helicobacter-pylori MH - Alpha-tocopherol MH - Ascorbic-acid MH - Lung-cancer MH - Vitamin-c MH - Follow-up MH - Atrophic gastritis MH - Stomach-cancer. AB - Data on blood levels of specific carotenoids and vitamins in relation to gastric cancer are scarce. Little is known about the relationship between prediagnostic serum levels of carotenoids other than beta-carotene and risk of gastric cancer especially in non-Western populations. Prediagnostic serum concentrations of alpha-carotene, beta-carotene, beta-cryptoxanthin, lycopene, lutein/ zeaxanthin, retinol, alpha-tocopherol, gamma-tocopherol, and vitamin C were determined on 191 cases and 570 matched controls within a cohort of 18,244 middle-aged or older men in Shanghai, China, with a follow-up of 12 years. High serum levels of alpha-carotene, beta-carotene, and lycopene were significantly associated with reduced risk of developing gastric cancer (all Ps for trend less than or equal to 0.05); the odds ratios (95% confidence intervals) for the highest versus the lowest quartile of (alpha-carotene, beta-carotene, and lycopene were 0.38 (0.13-1.11), 0.54 (0.32-0.89), and 0.55 (0.30-1.00), respectively. Increased serum level of vitamin C was significantly associated with reduced risk of gastric cancer among men who neither smoked cigarettes over lifetime nor consumed greater than or equal to 3 drinks of alcohol per day, the odds ratios (95% confidence intervals) for the second, third, and fourth quartile categories were 0.69 (0.28-1.70), 0.36 (0.14-0.94), and 0.39 (0.15-0.98), respectively, compared with the lowest quartile of vitamin C (P for trend = 0.02). There were no statistically significant relationships of serum levels of beta-cryptoxanthin, lutein/zeaxanthin, retinol, alpha-tocopherol, and gamma-tocopherol with gastric cancer risk. The present study implicates that dietary carotenes, lycopene, and vitamin C are potential chemopreventive agents for gastric cancer in humans. [References: 51] LG - English PT - Article SB - Current Contents(R)/Clinical Medicine Current Contents(R)/Life Sciences CC - Oncology in Current Contents(R)/Clinical Medicine. Oncogenesis & Cancer Research in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Yuan JM Univ So Calif, Dept Prevent Med, Kenneth Norris Jr Comprehens Canc Ctr, Keck Sch Med MC 9175,1441 Eastlake Ave Los Angeles, CA 90033 USA Univ So Calif, Dept Prevent Med, Kenneth Norris Jr Comprehens Canc Ctr, Keck Sch Med Los Angeles, CA 90033 USA Shanghai Canc Inst, Dept Epidemiol Shanghai Peoples R China Shanghai Canc Inst, Dept Carcinogenesis Shanghai Peoples R China <41> UI - 869UE-0008 DD - ISI Document Solution: 869UE AU - Wang CL AU - Xing D AU - Chen Q MA - xingda@scnu.edu.cn RA - Xing D TI - A novel method for measuring photosynthesis using delayed fluorescence of chloroplast SO - Biosensors & Bioelectronics. 20(3):454-459, 2004 Oct 15. AS - Biosens. Bioelectron 2004 Oct 15;20(3):454-459 PU - ELSEVIER ADVANCED TECHNOLOGY, OXFORD FULFILLMENT CENTRE THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND. URL: http://www.elsevier.nl IS - 0956-5663 MH - Biosensor MH - Delayed fluorescence MH - Photosynthesis ability MH - Photosynthesis rate. MH - Spinach-chloroplasts MH - Light-emission. AB - Photosynthesis is the most important chemical reaction in the world. The measurement of plant photosynthesis rate plays an important role in agriculture. Light-induced delayed fluorescence (DF) in plants is an intrinsic label of the efficiency of charge separation at P-680 in photosystem II (PS II). In this paper, we have developed a biosensor that can accurately measure the plant photosynthesis ability by means of DF. Compared with common methods for measuring the photosynthesis rate based on consumption Of CO2, the proposed technique can quantify the plant photosynthesis ability with less influence of the environment. The biosensor is an all-weather measuring instrument, it has its own illumination power and utilizes intrinsic DF as the measurement marker. The current investigation has revealed that, there is a good correspondence between the results measured by the biosensor and that by commercially available portable photosynthesis system under controlled conditions. We thus conclude that DF is an excellent marker for evaluating plant photosynthesis ability under its biological status with less interferences of the environment. (C) 2004 Elsevier B.V. All rights reserved. [References: 19] LG - English PT - Article SB - Current Contents(R)/Agriculture, Biology & Environmental Sciences CC - Biotechnology & Applied Microbiology in Current Contents(R)/Agricultural, Biology & Environmental Sciences. EW - 2005 week 01 IN - Reprint available from: Xing D S China Normal Univ, Inst Laser Life Sci Guangzhou 510631 Peoples R China S China Normal Univ, Inst Laser Life Sci Guangzhou 510631 Peoples R China <42> UI - 871MR-0001 DD - ISI Document Solution: 871MR AU - Ferrari CKB MA - drcarlosferrari@hotmail.com RA - Ferrari CKB TI - Functional foods, herbs and nutraceuticals: towards biochemical mechanisms of healthy aging [Review] SO - Biogerontology. 5(5):275-289, 2004 Oct. AS - Biogerontology 2004 Oct;5(5):275-289 PU - KLUWER ACADEMIC PUBL, VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS. URL: http://www.wkap.nl IS - 1389-5729 MH - Antioxidants MH - Chocolate MH - Dna oxidation MH - Garlic MH - Ginkgo biloba MH - Lycopene MH - Soy isoflavones MH - Tea MH - Wine. MH - Ginkgo-biloba extract MH - Hepatic mitochondrial-dna MH - Free-radical production MH - Coronary-heart-disease MH - Whole-grain intake MH - Egb 761 protects MH - Oxidative stress MH - Lipid-peroxidation MH - Breast-cancer MH - Cytochrome-c. AB - Aging is associated with mitochondrial dysfunctions, which trigger membrane leakage, release of reactive species from oxygen and nitrogen and subsequent induction of peroxidative reactions that result in biomolecules' damaging and releasing of metals with amplification of free radicals discharge. Free radicals induce neuronal cell death increasing tissue loss, which could be associated with memory detriment. These pathological events are involved in cardiovascular, neurodegenerative and carcinogenic processes. Dietary bioactive compounds from different functional foods, herbs and nutraceuticals (ginseng, ginkgo, nuts, grains, tomato, soy phytoestrogens, curcumin, melatonin, polyphenols, antioxidant vitamins, carnitine, carnosine, ubiquinone, etc.) can ameliorate or even prevent diseases. Protection from chronic diseases of aging involves antioxidant activities, mitochondrial stabilizing functions, metal chelating activities, inhibition of apoptosis of vital cells, and induction of cancer cell apoptosis. Functional foods and nutraceuticals constitute a great promise to improve health and prevent aging-related chronic diseases. [References: 152] LG - English PT - Review SB - Current Contents(R)/Life Sciences CC - Medical Research, General Topics in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Ferrari CKB Univ Sao Paulo, Fac Publ Hlth, Dept Nutr Av Dr Arnaldo 715,2 Andar BR-01246904 Sao Paulo Brazil Univ Sao Paulo, Fac Publ Hlth, Dept Nutr BR-01246904 Sao Paulo Brazil <43> UI - 868UQ-0002 DD - ISI Document Solution: 868UQ AU - Sigfridsson KGV AU - Bernat G AU - Mamedov F AU - Styring S MA - stenbjorn.styring@biokem.lu.se RA - Styring S TI - Molecular interference of Cd2+ with Photosystem II SO - Biochimica et Biophysica Acta - Bioenergetics. 1659(1):19-31, 2004 Nov 4. AS - Biochim. Biophys. Acta-Bioenerg 2004 Nov 4;1659(1):19-31 PU - ELSEVIER SCIENCE BV, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS. URL: http://www.elsevier.nl IS - 0005-2728 MH - Cadmium MH - Calcium MH - Dcmu MH - Epr MH - Fluorescence MH - Photosystem ii. MH - Electron-paramagnetic-res MH - Bacterial reaction centers MH - Oxygen-evolving complex MH - Cytochrome b(559) MH - Proton-transfer MH - Manganese cluster MH - Transport properties MH - Crystal-structure MH - Protein-turnover MH - Quinone acceptor. AB - Many heavy metals inhibit electron transfer reactions in Photosystem II (PSII). Cd2+ is known to exchange, with high affinity in a slow reaction, for the Ca2+ cofactor in the Ca/Mn cluster that constitutes the oxygen-evolving center. This results in inhibition of photosynthetic oxygen evolution. There are also indications that Cd2+ binds to other sites in PSII, potentially to proton channels in analogy to heavy metal binding in photosynthetic reaction centers from purple bacteria. In search for the effects of Cd2+-binding to those sites, we have studied how Cd2+ affects electron transfer reactions in PSII after short incubation times and in sites, which interact with Cd2+ with low affinity. Overall electron transfer and partial electron transfer were studied by a combination of EPR spectroscopy of individual redox components, flash-induced variable fluorescence and steady state oxygen evolution measurements. Several effects of Cd2+ were observed: (i) the amplitude of the flash-induced variable fluorescence was lost indicating that electron transfer from Y-Z to P-680(+) was inhibited; (ii) Q(A)(-) to Q(B) electron transfer was slowed down; (iii) the S-2 state multiline EPR signal was not observable; (iv) steady state oxygen evolution was inhibited in both a high-affinity and a low-affinity site; (v) the spectral shape of the EPR signal from Q(A)(-)Fe(2+) was modified but its amplitude was not sensitive to the presence of Cd2+. In addition, the presence of both Ca2+ and DCMU abolished Cd2+-induced effects partially and in different sites. The number of sites for Cd2+ binding and the possible nature of these sites are discussed. (C) 2004 Elsevier B.V. All rights reserved. [References: 59] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Biochemistry & Biophysics in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Styring S Lund Univ, Ctr Chem & Chem Engn, Dept Biochem POB 124 S-22100 Lund Sweden Lund Univ, Ctr Chem & Chem Engn, Dept Biochem S-22100 Lund Sweden <44> UI - 868UQ-0005 DD - ISI Document Solution: 868UQ AU - Di Pancrazio F AU - Mavelli I AU - Isola M AU - Losano G AU - Pagliaro P AU - Harris DA AU - Lippe G MA - glippe@makek.dstb.uniud.it RA - Lippe G TI - In vitro and in vivo studies of F(0)F(1)ATP synthase regulation by inhibitor protein IF1 in goat heart SO - Biochimica et Biophysica Acta - Bioenergetics. 1659(1):52-62, 2004 Nov 4. AS - Biochim. Biophys. Acta-Bioenerg 2004 Nov 4;1659(1):52-62 PU - ELSEVIER SCIENCE BV, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS. URL: http://www.elsevier.nl IS - 0005-2728 MH - Inhibitor protein if1 MH - Mitochondrial f0f1atp synthase MH - Ischemic preconditioning MH - Goat heart MH - Reactive hyperemia MH - Blue native polyacrylamide electrophoresis. MH - Mitochondrial oxidative-phosphorylation MH - Adenosine triphosphatase-inhibitor MH - Bovine heart MH - Protonic inhibition MH - Reactive hyperemia MH - Partial resolution MH - Cardiac-muscle MH - Atp synthesis MH - Rat hearts MH - F1-atpase. AB - A method has been developed to allow the level of F(0)F(1)ATP synthase capacity and the quantity of IF1 bound to this enzyme be measured in single biopsy samples of goat heart. ATP synthase capacity was determined from the maximal mitochondrial ATP hydrolysis rate and IF1 content was determined by detergent extraction followed by blue native gel electrophoresis, two-dimensional SDS-PAGE and immunoblotting with anti-IF1 antibodies. Anaesthetized open-chest goats were subjected to ischemic preconditioning and/or sudden increases of coronary blood flow (CBF) (reactive hyperemia). When hyperemia was induced before ischemic preconditioning, a steep increase in synthase capacity, followed by a deep decrease, was observed. In contrast, hyperemia did not affect synthase capacity when applied after ischemic preconditioning. Similar effects could be produced in vitro by treatment of heart biopsy samples with anoxia (down-regulation of the ATP synthase) or high-salt or high-pH buffers (up-regulation). We show that both in vitro and in vivo the same close inverse correlation exists between enzyme activity and IF1 content, demonstrating that under all conditions tested the only significant modulator of the enzyme activity was IF1. In addition, both in vivo and in vitro, 1.3 - 1.4 mol of IF1 was predicted to fully inactivate 1 mol of synthase, thus excluding the existence of significant numbers of non-inhibitory binding sites for IF1 in the F-0 sector. (C) 2004 Elsevier B.V. All rights reserved. [References: 40] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Biochemistry & Biophysics in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Lippe G Univ Udine, Dept Biomed Sci & Technol Ple Kolbe 4 I-33100 Udine Italy Univ Udine, Dept Biomed Sci & Technol I-33100 Udine Italy Univ Udine, MATI Ctr Excellence I-33100 Udine Italy Univ Udine, Sect Anat, Dept Med & Morphol Researches I-33100 Udine Italy Univ Turin, Sect Physiol, Dept Neurosci, Sect Physiol I-10125 Turin Italy Univ Turin, Sect Physiol, Dept Clin & Biol Sci I-10125 Turin Italy Univ Oxford, Dept Biochem Oxford OX1 3QU England <45> UI - 868UQ-0006 DD - ISI Document Solution: 868UQ AU - Kirchhoff H AU - Schottler MA AU - Maurer J AU - Weis E MA - kirchhh@uni-muenster.de RA - Kirchhoff H TI - Plastocyanin redox kinetics in spinach chloroplasts: evidence for disequilibrium in the high potential chain SO - Biochimica et Biophysica Acta - Bioenergetics. 1659(1):63-72, 2004 Nov 4. AS - Biochim. Biophys. Acta-Bioenerg 2004 Nov 4;1659(1):63-72 PU - ELSEVIER SCIENCE BV, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS. URL: http://www.elsevier.nl IS - 0005-2728 MH - Plastocyanin MH - Redox equilibrium MH - Thylakoids MH - Diffusion. MH - Photosynthetic electron-transport MH - Induced absorbency changes MH - Photosystem-i MH - Cytochrome-f MH - Higher-plants MH - Thylakoids MH - Complex MH - Leaves MH - Flow MH - Ph. AB - Reduction kinetics of cytochrome f, plastocyanin (PC) and P-700 (`high-potential chain') in thylakoids from spinach were followed after pre-oxidation by a saturating light pulse. We describe a novel approach to follow PC redox kinetics from deconvolution of 810-860 nm absorption changes. The equilibration between the redox-components was analyzed by plotting the redox state of cytochrome f and PC against that of P-700. In thylakoids with (1) diminished electron transport rate (adjusted with a cytochrome bf inhibitor) or (2) de-stacked grana, cytochrome f and PC relaxed close to their thermodynamic equilibriums with P-700. In stacked thylakoids with non-inhibited electron transport, the equilibration plots were complex and non-hyperbolic, suggesting that during fast electron flux, the `high-potential chain' does not homogeneously equilibrate throughout the membrane. Apparent equilibrium constants <5 were calculated, which are below the thermodynamic equilibrium known for the `high potential chain'. The disequilibrium found in stacked thylakoids with high electron fluxes is explained by restricted long-range PC diffusion. We develop a model assuming that about 30% of Photosystem I mainly located in grana end-membranes and margins rapidly equilibrate with cytochrome f via short-distance transluminal PC diffusion, while long-range lateral PC migration between grana cores and distant stroma lamellae is restricted. Implications for the electron flux control are discussed. (C) 2004 Elsevier B.V. All rights reserved. [References: 43] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Biochemistry & Biophysics in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Kirchhoff H Inst Bot Schlossgarten 3 D-48149 Munster Germany Inst Bot D-48149 Munster Germany <46> UI - 868UQ-0009 DD - ISI Document Solution: 868UQ AU - Tittingdorf JMWMZ AU - Rexroth S AU - Schafer E AU - Schlichting R AU - Giersch C AU - Dencher NA AU - Seelert H MA - nad@pop.tu-darmstadt.de, seelert@hrzpub.tu-darmstadt.de RA - Dencher NA TI - The stoichiometry of the chloroplast ATP synthase oligomer III in Chlamydomonas reinhardtii is not affected by the metabolic state SO - Biochimica et Biophysica Acta - Bioenergetics. 1659(1):92-99, 2004 Nov 4. AS - Biochim. Biophys. Acta-Bioenerg 2004 Nov 4;1659(1):92-99 PU - ELSEVIER SCIENCE BV, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS. URL: http://www.elsevier.nl IS - 0005-2728 MH - Atp synthase MH - Oligomer iii MH - Stoichiometry MH - Chloroplast MH - Metabolic state. MH - Escherichia-coli MH - Molecular architecture MH - Thylakoid membrane MH - Undecameric rotor MH - Rotary motor MH - H+/atp ratio MH - Subunit-iii MH - F1f0 atpase MH - C-subunit MH - Mitochondria. AB - The chloroplast H+-ATP synthase is a key component for the energy supply of higher plants and green algae. An oligomer of identical protein subunits III is responsible for the conversion of an electrochemical proton gradient into rotational motion. It is highly controversial if the oligomer III stoichiometry is affected by the metabolic state of any organism. Here, the intact oligomer III of the ATP synthase from Chlamydomonas reinhardtii has been isolated for the first time. Due to the importance of the subunit III stoichiometry for energy conversion, a gradient gel system was established to distinguish oligomers with different stoichiometries. With this methodology, a possible alterability of the stoichiometry in respect to the metabolic state of the cells was examined. Several growth parameters, i.e., light intensity, pH value, carbon source, and CO2 concentration, were varied to determine their effects on the stoichiometry. Contrary to previous suggestions for E. coli, the oligomer III of the chloroplast H+-ATP synthase always consists of a constant number of monomers over a wide range of metabolic states. Furthermore, mass spectrometry indicates that subunit III from C. reinhardtii is not modified posttranslationally. Data suggest a subunit III stoichiometry of the algae ATP synthase divergent from higher plants. (C) 2004 Elsevier B.V. All rights reserved. [References: 37] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Biochemistry & Biophysics in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Dencher NA Tech Univ Darmstadt, Dept Chem Phys Biochem Petersenstr 22 D-64287 Darmstadt Germany Tech Univ Darmstadt, Dept Chem Phys Biochem D-64287 Darmstadt Germany Tech Univ Darmstadt, Inst Bot D-64287 Darmstadt Germany <47> UI - 868UQ-0010 DD - ISI Document Solution: 868UQ AU - Cadoret JC AU - Demouliere R AU - Lavaud J AU - van Gorkom HJ AU - Houmard J AU - Etienne AL MA - jhoumard@biologie.ens.fr RA - Houmard J TI - Dissipation of excess energy triggered by blue light in cyanobacteria with CP43 ' (isiA) SO - Biochimica et Biophysica Acta - Bioenergetics. 1659(1):100-104, 2004 Nov 4. AS - Biochim. Biophys. Acta-Bioenerg 2004 Nov 4;1659(1):100-104 PU - ELSEVIER SCIENCE BV, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS. URL: http://www.elsevier.nl IS - 0005-2728 MH - Non-photochemical quenching MH - Iron-stress MH - Chlorophyll antenna MH - Photoprotection MH - Photosystems. MH - Chlorophyll-protein complex MH - Synechococcus sp pcc7942 MH - Photosystem-ii MH - Fluorescence MH - Diadinoxanthin MH - System MH - Gene. AB - The chlorophyll-protein CP43' (isiA gene) induced by stress conditions in cyanobacteria is shown to serve as an antenna for Photosystem II (PSII), in addition to its known role as an antenna for Photosystem I (PSI). At high light intensity, this antenna is converted to an efficient trap for chlorophyll excitations that protects system II from photo-inhibition. In contrast to the `energy-dependent non-photochemical quenching' (NPQ) in chloroplasts, this photoprotective energy dissipation in cyanobacteria is triggered by blue light. The induction is proportional to light intensity. Induction and decay of the quenching exhibit the same large temperature-dependence. (C) 2004 Elsevier B.V. All rights reserved. [References: 21] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Biochemistry & Biophysics in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Houmard J CNRS, Dept Biol, FRE 2433 46 Rue Ulm F-75230 Paris 05 France CNRS, Dept Biol, FRE 2433 F-75230 Paris 05 France Univ Konstanz, Dept Biol D-78457 Constance Germany Leiden Univ, Dept Biophys NL-2300 RA Leiden Netherlands <48> UI - 868UV-0030 DD - ISI Document Solution: 868UV AU - Clark RW AU - Youn H AU - Parks RB AU - Cherney MM AU - Roberts GP AU - Burstyn JN MA - burstyn@chem.wisc.edu RA - Burstyn JN TI - Investigation of the role of the N-terminal proline, the distal heme ligand in the CO sensor CooA SO - Biochemistry. 43(44):14149-14160, 2004 Nov 9. AS - Biochemistry 2004 Nov 9;43(44):14149-14160 PU - AMER CHEMICAL SOC, 1155 16TH ST, NW, WASHINGTON, DC 20036 USA. URL: http://pubs.acs.org IS - 0006-2960 MH - Magnetic circular-dichroism MH - Electron-paramagnetic-resonance MH - Sensing transcriptional activator MH - Soluble guanylate-cyclase MH - Carbon-monoxide complex MH - Nitric-oxide synthase MH - Rhodospirillum-rubrum MH - Cytochrome p-450cam MH - Binding-properties MH - Thiolate ligation. AB - A unique feature of CooA, a heme-containing transcription factor, is that the N-terminal proline is the distal heme ligand in the ferrous state, and this ligand is displaced upon CO binding. To investigate the importance of Pro(2) in CO-dependent DNA binding, several CooA variants that alter N-terminal ligation were characterized. Electronic absorption, electron paramagnetic resonance, and magnetic circular dichroism spectra of these variants provide the most definitive evidence that Pro(2) is the distal ligand in Fe(III) CooA. Furthermore, the functional and spectroscopic properties of these proteins depended on whether a weak ligand occupied the distal heme coordination site: for CooA variants in which distal coordination is disrupted, the DNA-binding affinities and Fe(II)-CO spectral properties showed an unexpected dependence on the order of CO addition and heme reduction. If N-terminal variant samples were incubated with CO before the heme was reduced, the proteins displayed DNA-binding affinities and Fe(II)-CO spectral characteristics similar to those of wild-type (WT) CooA. However, if the same samples were incubated with CO after the heme was reduced, the extent of functional and spectral similarity to WT CooA negatively correlated with the amount of high-spin heme present in the ferric state. From these data, it was inferred that the absence of a distal heme ligand in the ferric state prevents WT-like CO binding to the ferrous state, and it was hypothesized that correct CO binding is inhibited by the collapse of the distal heme pocket upon reduction. Together with the observation that L116H CooA, a variant in which His(116) replaces Pro(2) as the distal heme ligand, binds CO more slowly than WT CooA, these data indicate that the presence of a weak distal heme ligand, not specifically ligation by the N-terminal proline, is crucial for proper function. The role of Pro(2) in CooA is apparently to direct CO to bind on the distal side of heme and to help maintain the integrity of the distal heme pocket during the redox-mediated ligand switch. [References: 61] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Biochemistry & Biophysics in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Burstyn JN Univ Wisconsin, Dept Chem 1101 Univ Ave Madison, WI 53706 USA Univ Wisconsin, Dept Chem Madison, WI 53706 USA Univ Wisconsin, Dept Bacteriol Madison, WI 53706 USA <49> UI - 868UV-0031 DD - ISI Document Solution: 868UV AU - Li ZL AU - Andrews H AU - Eaton-Rye JJ AU - Burnap RL MA - burnap@biochem.okstate.edu RA - Burnap RL TI - In situ effects of mutations of the extrinsic cytochrome c(550) of photosystem II in Synechocystis sp PCC6803 SO - Biochemistry. 43(44):14161-14170, 2004 Nov 9. AS - Biochemistry 2004 Nov 9;43(44):14161-14170 PU - AMER CHEMICAL SOC, 1155 16TH ST, NW, WASHINGTON, DC 20036 USA. URL: http://pubs.acs.org IS - 0006-2960 MH - Manganese-stabilizing protein MH - Photosynthetic oxygen-evolution MH - Cyanobacterium thermosynechococcus-elongatus MH - Axial ligand replacement MH - Blue-green-alga MH - A-b loop MH - Sp pcc-6803 MH - Evolving complex MH - Crystal-structure MH - Heme-iron. AB - The H2O oxidizing domain of the cyanobacterial photosystem II (PSII) complex contains a low potential, c-type cytochrome termed c(550) that is essential for the in vivo stability of the PSII complex. A mutant lacking cytochrome c(550) (DeltapsbV) in Synechocystis sp. PCC6803 has been further analyzed together with a construct in which the distal axial heme iron ligand, histidine 92, has been substituted with a methionine (C550-H92M). Heme staining of SDS-PAGE showed that the C550-H92M mutation did not disturb the accumulation and heme-binding properties of the cytochrome. In DeltapsbV cells, the number of charge separating PSII centers was estimated to be 56% of the wild type, but of the existing centers, 33% lacked photooxidizable Mn ions. C550-H92M did not discernibly affect the intrinsic PSII electron-transfer kinetics compared to the wild type nor did it exhibit a significant fraction of centers lacking photooxidizable Mn; however, the number of charge separating PSII centers in mutant cells was 69% of the wild type. C550-H92M lost photoautotrophic growth ability in the absence of Ca2+, but its growth was not affected by depletion of CI-, which differs from DeltapsbV. Taken together, the results suggest that in the absence of cytochrome c(550) electron transfer on the donor side is retarded perhaps at the level of Y-z to P680(divided by) transfer, the heme ligand. His92 is not absolutely required for assembly of functional PSII centers; however, replacement by methionine prevents normal accumulation of PSII centers in the thylakoid membranes and alters the Ca2+ requirement of PSIL The results are discussed in terms of current understanding of the Ca2+ site of PSII. [References: 81] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Biochemistry & Biophysics in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Burnap RL Oklahoma State Univ, Dept Microbiol & Mol Genet Stillwater, OK 74078 USA Oklahoma State Univ, Dept Microbiol & Mol Genet Stillwater, OK 74078 USA Univ Otago, Dept Biochem Dunedin New Zealand <50> UI - 868UV-0035 DD - ISI Document Solution: 868UV AU - Francia F AU - Dezi M AU - Rebecchi A AU - Mallardi A AU - Palazzo G AU - Melandri BA AU - Venturoli G MA - francia@alma.unibo.it RA - Francia F TI - Light-harvesting complex 1 stabilizes P(+)Q(B)(-) charge separation in reaction centers of Rhodobacter sphaeroides SO - Biochemistry. 43(44):14199-14210, 2004 Nov 9. AS - Biochemistry 2004 Nov 9;43(44):14199-14210 PU - AMER CHEMICAL SOC, 1155 16TH ST, NW, WASHINGTON, DC 20036 USA. URL: http://pubs.acs.org IS - 0006-2960 MH - Bacterial reaction centers MH - Photosynthetic reaction centers MH - Electron-transfer kinetics MH - Free-energy dependence MH - Rhodopseudomonas-sphaeroides MH - Extinction coefficients MH - Secondary quinone MH - Crystal-structure MH - Purple bacteria MH - Transfer chain. AB - The kinetics of charge recombination following photoexcitation by a laser pulse have been analyzed in the reaction center-light harvesting complex 1 (RC-LH1) purified from the photosynthetic bacterium Rhodobacter sphaeroides. In RC-LH1 core complexes isolated from photosynthetically grown cells P(divided by)Q(B)(-) recombines with an average rate constant, approximate to 0.3 s(-1), more than three times smaller than that measured in RC deprived of the LH1 ( approximate to 1 s(-1)). A comparable, slowed recombination kinetics is observed in RC-LH1 complexes purified from a pufX-deleted strain. Slowing of the charge recombination kinetics is even more pronounced in RC-LH1 complexes isolated from wild-type semiaerobically grown cells ( approximate to 0.2 s(-1)). Since the kinetics of P(+)Q(A)(-) recombination is unaffected by the presence of the antenna, the P+Q(B)(-) state appears to be energetically stabilized in core complexes. Determinations of the ubiquinone-10 (UQ(10)) complement associated with the purified RC-LH1 complexes always yield UQ(10)/ RC ratios larger than 10. These quinone molecules are functionally coupled to the RC-LH1 complex, as judged from the extent of exogenous cytochrome c(2) rapidly oxidized under continuous light excitation. Analysis of P(divided by)Q(B)(-) recombination, based on a kinetic model which considers fast quinone equilibrium at the Q(B) binding site, indicates that the slowing down of charge recombination kinetics observed in RC-LH1 complexes cannot be explained solely by a quinone concentration effect and suggests that stabilization of the light-induced charge separation is predominantly due to interaction of the QB site with the LH1 complex. The high UQ(10) complements detected in RC-LH1 core complexes, but not in purified light harvesting complex 2 and in RC, are proposed to reflect an in vivo heterogeneity in the distribution of the quinone pool within the chromatophore bilayer. [References: 69] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Biochemistry & Biophysics in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Francia F Univ Bologna, Lab Biochim & Biofis, Dipartimento Biol I-40126 Bologna Italy Univ Bologna, Lab Biochim & Biofis, Dipartimento Biol I-40126 Bologna Italy CNR, Ist Proc ChimicoFis I-70126 Bari Italy Univ Bari, Dipartimento Chim I-70126 Bari Italy Ist Nazl Fis Mat, UdR Bologna I-40127 Bologna Italy <51> UI - 870YO-0008 DD - ISI Document Solution: 870YO AU - Narvaez AJ AU - LoBrutto R AU - Allen JP AU - Williams JC MA - jallen@asu.edu RA - Allen JP TI - Trapped tyrosyl radical populations in modified reaction centers from Rhodobacter sphaeroides SO - Biochemistry. 43(45):14379-14384, 2004 Nov 16. AS - Biochemistry 2004 Nov 16;43(45):14379-14384 PU - AMER CHEMICAL SOC, 1155 16TH ST, NW, WASHINGTON, DC 20036 USA. URL: http://pubs.acs.org IS - 0006-2960 MH - Photosynthetic reaction centers MH - Site-directed mutagenesis MH - Oxygen-evolving complex MH - Amino-acid-residues MH - Photosystem-ii MH - Manganese cluster MH - Water oxidation MH - Y-z MH - Electron-transfer MH - Proton release. AB - The photosynthetic reaction center from the purple bacterium Rhodobacter sphaeroides has been modified such that the bacteriochlorophyll dimer, when it becomes oxidized after light excitation, is capable of oxidizing tyrosine residues. One factor in this ability is a high oxidation-reduction midpoint potential for the dimer, although the location and protein environment of the tyrosine residue appear to be critical as well. These factors were tested in a series of mutants, each of which contains changes, at residues L131, M160, M197, and M210, that give rise to a bacteriochlorophyll dimer with a midpoint potential of at least 800 mV. The protein environment was altered near tyrosine residues that are either present in the wild type or introduced by mutagenesis, focusing on residues that could act as acceptors for the phenolic proton of the tyrosine upon oxidation. These mutations include Ser M 190 to His, which is near Tyr L 162, the combination of His M 193 to Tyr and Arg M 164 to His, which adds a Tyr- His pair, and the combinations of Arg L135 to Tyr with Tyr L164 to His, Arg L135 to Tyr with Tyr L144 to Glu, and Arg L135 to Tyr with Tyr L164 to Phe. Radicals were produced in the mutants by using light to initiate electron transfer. The radicals were trapped by freezing the samples, and the relative populations of the oxidized dimer and tyrosyl radicals were determined by analysis of low-temperature electron paramagnetic resonance spectra. The mutants all showed evidence of tyrosyl radical formation at high pH, and the extent of radical formation at Tyr L 135 with pH differed depending on the identity of L 144 and L164. The results show that tyrosine residues within approximately 10 A of the dimer can become oxidized when provided with a suitable protein environment. [References: 29] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Biochemistry & Biophysics in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Allen JP Arizona State Univ, Dept Chem & Biochem Tempe, AZ 85287 USA Arizona State Univ, Dept Chem & Biochem Tempe, AZ 85287 USA Arizona State Univ, Sch Life Sci Tempe, AZ 85287 USA <52> UI - 870YO-0021 DD - ISI Document Solution: 870YO AU - Kirchhoff H AU - Borinski M AU - Lenhert S AU - Chi LF AU - Buchel C MA - kirchhh@uni-muenster.de RA - Kirchhoff H TI - Transversal and lateral exciton energy transfer in grana thylakoids of spinach SO - Biochemistry. 43(45):14508-14516, 2004 Nov 16. AS - Biochemistry 2004 Nov 16;43(45):14508-14516 PU - AMER CHEMICAL SOC, 1155 16TH ST, NW, WASHINGTON, DC 20036 USA. URL: http://pubs.acs.org IS - 0006-2960 MH - Light-harvesting complex MH - Scanning force microscopy MH - Photosystem-ii membranes MH - Fluorescence induction MH - Electron-transport MH - Chlorophyll-a MH - Cryoelectron microscopy MH - State transitions MH - Crystal-structure MH - Surface-charges. AB - The excitation energy transfer between photosystem (PS) II complexes was studied in isolated grana disks and thylakoids using chlorophyll a fluorescence induction measurements in the presence of DCMU under stacked and destacked conditions. Destacking of grana was achieved using a sonication protocol in a buffer without MgCl2. The degree of stacking was controlled and quantified by atomic force microscopy and by the concomitant absorption changes. As expected from the literature, intact thylakoids showed a strong dependency of the connectivity of PSII centers, the F-m/F-o. ratio as well as the fraction of PSIIbeta centers on the MgCl2 concentration. In contrast, these parameters did not change in isolated grana disks. In particular, the connectivity remained constantly high irrespective of the degree of destacking. These differences were explained by the high protein density in grana disks, which hinders separation and mixing of proteins sufficiently to change energy transfer properties. Due to the occurrence of stroma lamella in intact thylakoids, intermixing of PSII and PSI is possible and allows for changes in F-m/F-o ratio as is the separation of LHCII from PSII, thus leading to an increase in the fraction of PSIIbeta. Even if mixing and separation of proteins are impaired in isolated grana disks, destacking should lead to a decrease in connectivity if transversal excitation energy transfer between two opposite membranes is significant. Because the connectivity is constant over all degrees of destacking employed, we conclude that the energy transfer in granas is mainly lateral. [References: 61] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Biochemistry & Biophysics in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Kirchhoff H Inst Bot Schlossgarten 3 D-48149 Munster Germany Inst Bot D-48149 Munster Germany Inst Phys D-48149 Munster Germany Max Planck Inst Biophys D-60439 Frankfurt Germany <53> UI - 871YO-0019 DD - ISI Document Solution: 871YO AU - Pazicni S AU - Lukat-Rodgers GS AU - Oliveriusova J AU - Rees KA AU - Parks RB AU - Clark RW AU - Rodgers KR AU - Kraus JP AU - Burstyn JN MA - burstyn@chem.wisc.edu RA - Burstyn JN TI - The redox behavior of the heme in cystathionine beta-synthase is sensitive to pH SO - Biochemistry. 43(46):14684-14695, 2004 Nov 23. AS - Biochemistry 2004 Nov 23;43(46):14684-14695 PU - AMER CHEMICAL SOC, 1155 16TH ST, NW, WASHINGTON, DC 20036 USA. URL: http://pubs.acs.org IS - 0006-2960 MH - Magnetic circular-dichroism MH - Resonance raman-spectroscopy MH - Sensing transcription factor MH - Purified guanylate-cyclase MH - Active-site structure MH - Oxygen sensor fixl MH - Rhodospirillum-rubrum MH - Nitric-oxide MH - Saccharomyces-cerevisiae MH - Escherichia-coli. AB - Human cystathionine beta-synthase (CBS) is a unique pyridoxal-5'-phosphate-dependent enzyme in which heme is also present as a cofactor. Because the function of heme in this enzyme has yet to be elucidated, the study presented herein investigated possible relationships between the chemistry of the heme and the strong pH dependence of CBS activity. This study revealed, via study of a truncation variant, that the catalytic core of the enzyme governs the pH dependence of the activity. The heme moiety was found to play no discernible role in regulating CBS enzyme activity by sensing changes in pH, because the coordination sphere of the heme is not altered by changes in pH over a range of pH 6-9. Instead, pH was found to control the equilibrium amount of ferric and ferrous heme present after reaction of CBS with one-electron reducing agents. A variety of spectroscopic techniques, including resonance Raman, magnetic circular dichroism, and electron paramagnetic resonance, demonstrated that at pH 9 Fe(II) CBS is dominant while at pH 6 Fe(III) CBS is favored. At low pH, Fe(II) CBS forms transiently but reoxidizes by an apparent proton-gated electron-transfer mechanism. Regulation of CBS activity by the iron redox state has been proposed as the role of the heme moiety in this enzyme. Given that the redox behavior of the CBS heme appears to be controlled by pH, interplay of pH and oxidation state effects must occur if CBS activity is redox regulated. [References: 72] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Biochemistry & Biophysics in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Burstyn JN Univ Wisconsin, Dept Chem 1101 Univ Ave Madison, WI 53706 USA Univ Wisconsin, Dept Chem Madison, WI 53706 USA N Dakota State Univ, Dept Chem Fargo, ND 58105 USA Univ Colorado, Sch Med, Dept Pediat & Cellular & Struct Biol Denver, CO 80262 USA <54> UI - 871YO-0021 DD - ISI Document Solution: 871YO AU - Mick V AU - Geister S AU - Paulsen H MA - paulsen@mail.uni-mainz.de RA - Paulsen H TI - The folding state of the lumenal loop determines the thermal stability of light-harvesting chlorophyll a/b protein SO - Biochemistry. 43(46):14704-14711, 2004 Nov 23. AS - Biochemistry 2004 Nov 23;43(46):14704-14711 PU - AMER CHEMICAL SOC, 1155 16TH ST, NW, WASHINGTON, DC 20036 USA. URL: http://pubs.acs.org IS - 0006-2960 MH - Membrane-protein MH - Pigment-binding MH - 2-stage model MH - Amino-acids MH - Side-chains MH - In-vitro MH - Complex MH - Bacteriorhodopsin MH - Reconstitution MH - Transmembrane. AB - The major light-harvesting protein of photosystem II (LHCIIb) is the most abundant chlorophyll-binding protein in the thylakoid membrane. It contains three membrane-spanning alpha helices; the first and third one closely interact with each other to form a super helix, and all three helices bind most of the pigment cofactors. The protein loop domains connecting the alpha helices also play an important role in stabilizing the LHCIIb structure. Single amino acid exchanges in either loop were found to be sufficient to significantly destabilize the complex assembled in vitro [Heinemann, B., and Paulsen, H. (1999) Biochemistry 38, 14088-14093. Mick, V., Eggert, K., Heinemann, B., Geister, S., and Paulsen, H (2004) Biochemistry 43, 5467-5473]. This work presents an analysis of such point mutations in the lumenal loop with regard to the extent and nature of their effect on LHCIIb stability to obtain detailed information on the contribution of this loop to stabilizing the complex. Most of the mutant proteins yielded pigment-protein complexes if their reconstitution and/or isolation was performed under mild conditions; however, the yields were significantly different. Several mutations in the vicinity of W97 in the N-proximal section of the loop gave low reconstitution yields even under very mild conditions. This confirms our earlier notion that W97 may be of particular relevance in stabilizing LHCIIb. The same amino acid exchanges accelerated thermal complex dissociation in the absence of lithium dodecyl sulfate (LDS) and raised the accessibility of the lumenal loop to protease; both effects were well correlated with the reduction in reconstitution yields. We conclude that a detachment of the lumenal loop is a possible first step in the dissociation of LHCIIb. Dramatically reduced complex yields in the presence but not in the absence of LDS were observed for some but not all mutants, particularly those near the C-proximal end of the loop. We conclude that complex stabilities in the absence and in the presence of LDS do not correlate and most likely are determined by different structural characteristics, at least in LHCIIb but maybe also in other membrane proteins. [References: 43] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Biochemistry & Biophysics in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Paulsen H Univ Mainz, Inst Allgemeine Bot D-55099 Mainz Germany Univ Mainz, Inst Allgemeine Bot D-55099 Mainz Germany <55> UI - 872RA-0009 DD - ISI Document Solution: 872RA AU - Nantapong N AU - Kugimiya Y AU - Toyama H AU - Adachi O AU - Matsushita K MA - kazunobu@yamaguchi-u.ac.jp RA - Matsushita K TI - Effect of NADH dehydrogenase-disruption and over-expression on respiration-related metabolism in Corynebacterium glutamicum KY9714 SO - Applied Microbiology & Biotechnology. 66(2):187-193, 2004 Dec. AS - Appl. Microbiol. Biotechnol 2004 Dec;66(2):187-193 PU - SPRINGER, 233 SPRING STREET, NEW YORK, NY 10013 USA. URL: http://www.springer-ny.com IS - 0175-7598 MH - Escherichia-coli MH - Ubiquinone oxidoreductases MH - Azotobacter-vinelandii MH - Nucleotide-sequence MH - Membrane-vesicles MH - Chain MH - Purification MH - Cytochrome MH - Oxidase MH - Transformation. AB - The function of type II NADH dehydrogenase (NDH-2) in Gram-positive Corynebacterium glutamicum was investigated by preparing strains with ndh, the NDH-2 gene, disrupted and over-expressed. Although disruption showed no growth defects on glucose minimum medium, the growth rate of the over-expressed strain was lower compared with its parent, C. glutamicum KY9714. Ndh-disruption and over-expression did not lead to a large change in the respiratory chain and energetics, including the cytochrome components and the H+/O ratio. However, in the strain that lacked NDH-2, membrane L-lactate oxidase activity increased, while NDH-2 over-expression led to decreased L-lactate and malate oxidase activities. In addition, relatively high cytoplasmic lactate dehydrogenase (LDH) activity was always present as was malate dehydrogenase, irrespective of NDH-2 level. Furthermore, L-lactate or malate-dependent NADH oxidase activity could be reproduced by reconstitution with the membranes and the cytoplasmic fraction isolated from the disruptant. These results suggest that coupling of LDH and the membrane L-lactate oxidase system, together with the malate-dependent NADH oxidase system, operates to oxidize NADH when the NDH-2 function is defective in C. glutamicum. [References: 28] LG - English PT - Article SB - Current Contents(R)/Agriculture, Biology & Environmental Sciences Current Contents(R)/Life Sciences CC - Biotechnology & Applied Microbiology in Current Contents(R)/Agricultural, Biology & Environmental Sciences. Microbiology in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Matsushita K Yamaguchi Univ, Fac Agr, Dept Biol Chem 1677-1 Yoshida Yamaguchi 7538511 Japan Yamaguchi Univ, Fac Agr, Dept Biol Chem Yamaguchi 7538511 Japan <56> UI - 870RR-0006 DD - ISI Document Solution: 870RR AU - Niamsiri N AU - Delamarre SC AU - Kim YR AU - Batt CA MA - cab10@cornell.edu RA - Batt CA TI - Engineering of chimeric class II polyhydroxyalkanoate synthases SO - Applied & Environmental Microbiology. 70(11):6789-6799, 2004 Nov. AS - Appl. Environ. Microbiol 2004 Nov;70(11):6789-6799 PU - AMER SOC MICROBIOLOGY, 1752 N ST NW, WASHINGTON, DC 20036-2904 USA. URL: http://www.asmusa.org IS - 0099-2240 MH - Beta-hydroxybutyric acid MH - In-vitro evolution MH - Ralstonia-eutropha MH - Polyhydroxybutyrate synthase MH - Pha synthase MH - Pseudomonas-aeruginosa MH - Rhodospirillum-rubrum MH - Chromatium-vinosum MH - Covalent catalysis MH - Molecular-basis. AB - PHA synthase is a key enzyme involved in the biosynthesis of polyhydroxyalkanoates (PHAs). Using a combinatorial genetic strategy to create unique chimeric class II PHA synthases, we have obtained a number of novel chimeras which display improved catalytic properties. To engineer the chimeric PHA synthases, we constructed a synthetic phaC gene from Pseudomonas oleovorans (phaC1(Po)) that was devoid of an internal 540-bp fragment. Randomly amplified PCR products (created with primers based on conserved phaC sequences flanking the deleted internal fragment) were generated using genomic DNA isolated from soil and were substituted for the 540-bp internal region. The chimeric genes were expressed in a PHA-negative strain of Ralstonia eutropha, PHB(-)4 (DSM 541). Out of 1,478 recombinant clones screened for PHA production, we obtained five different chimeric phaC1(Po) genes that produced more PHA than the native phaC1(Po). Chimeras S1-71, S4-8, S5-58, S3-69, and S3-44 exhibited 1.3-, 1.4-, 2.0-, 2.1-, and 3.0-fold-increased levels of in vivo activity, respectively. All of the mutants mediated the synthesis of PHAs with a slightly increased molar fraction of 3-hydroxyoctanoate; however, the weight-average molecular weights (M-w) of the PHAs in all cases remained almost the same. Based upon DNA sequence analyses, the various phaC fragments appear to have originated from Pseudomonas fluorescens and Pseudomonas aureofaciens. The amino acid sequence analyses showed that the chimeric proteins had 17 to 20 amino acid differences from the wild-type phaC1(Po), and these differences were clustered in the same positions in the five chimeric clones. A threading model of phaC1(Po), developed based on homology of the enzyme to the Burkholderia glumae lipase, suggested that the amino acid substitutions found in the active chimeras were located mostly on the protein model surface. Thus, our combinatorial genetic engineering strategy proved to be broadly useful for improving the catalytic activities of PHA synthase enzymes. [References: 33] LG - English PT - Article SB - Current Contents(R)/Agriculture, Biology & Environmental Sciences Current Contents(R)/Life Sciences CC - Biology in Current Contents(R)/Agricultural, Biology & Environmental Sciences. Microbiology in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Batt CA Cornell Univ, Dept Food Sci Stocking Hall Ithaca, NY 14853 USA Cornell Univ, Dept Food Sci Ithaca, NY 14853 USA Mahidol Univ, Fac Sci, Dept Biotechnol Bangkok 10700 Thailand <57> UI - 870RR-0031 DD - ISI Document Solution: 870RR AU - Borghese R AU - Borsetti F AU - Foladori P AU - Ziglio G AU - Zannoni D MA - roberto.borghese@unibo.it RA - Borghese R TI - Effects of the metalloid oxyanion tellurite (TeO32-) on growth characteristics of the phototrophic bacterium Rhodobacter capsulatus SO - Applied & Environmental Microbiology. 70(11):6595-6602, 2004 Nov. AS - Appl. Environ. Microbiol 2004 Nov;70(11):6595-6602 PU - AMER SOC MICROBIOLOGY, 1752 N ST NW, WASHINGTON, DC 20036-2904 USA. URL: http://www.asmusa.org IS - 0099-2240 MH - Rhodopseudomonas-capsulata MH - Potassium tellurite MH - Flow-cytometry MH - Rhodospirillum-rubrum MH - Resistance operon MH - Respiratory-chain MH - Escherichia-coli MH - Steady-state MH - Reduction MH - Cells. AB - This work examines the effects of potassium tellurite (K2TeO3) on the cell viability of the facultative phototroph Rhodobacter capsulatus. There was a growth mode-dependent response in which cultures anaerobically grown in the light tolerate the presence of up to 250 to 300 mug of tellurite (TeO32-) per ml, while dark-grown aerobic cells were inhibited at tellurite levels as low as 2 mug/ml. The tellurite sensitivity of aerobic cultures was evident only for growth on minimal salt medium, whereas it was not seen during growth on complex medium. Notably, through the use of flow cytometry, we show that the cell membrane integrity was strongly affected by tellurite during the early growth phase (less than or equal to50% viable cells); however, at the end of the growth period and in parallel with massive tellurite intracellular accumulation as elemental Te-0 crystallites, recovery of cytoplasmic membrane integrity was apparent ( greater than or equal to90% viable cells), which was supported by the development of a significant membrane potential (DeltaPsi = 120 mV). These data are taken as evidence that in anaerobic aquatic habitats, the facultative phototroph R. capsulatus might act as a natural scavenger of the highly soluble and toxic oxyanion tellurite. [References: 29] LG - English PT - Article SB - Current Contents(R)/Agriculture, Biology & Environmental Sciences Current Contents(R)/Life Sciences CC - Biology in Current Contents(R)/Agricultural, Biology & Environmental Sciences. Microbiology in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Borghese R Univ Bologna, Dipartimento Biol Via Irnerio 42 I-40126 Bologna Italy Univ Bologna, Dipartimento Biol I-40126 Bologna Italy Univ Trent, Dipartimento Ingn Civile & Ambientale Trento Italy <58> UI - 870RR-0077 DD - ISI Document Solution: 870RR AU - Demaneche S AU - Meyer C AU - Micoud J AU - Louwagie M AU - Willison JC AU - Jouanneau Y MA - yjouanneau@cea.fr RA - Jouanneau Y TI - Identification and functional analysis of two aromatic-ring-hydroxylating dioxygenases from a Sphingomonas strain that degrades various polycyclic aromatic hydrocarbons SO - Applied & Environmental Microbiology. 70(11):6714-6725, 2004 Nov. AS - Appl. Environ. Microbiol 2004 Nov;70(11):6714-6725 PU - AMER SOC MICROBIOLOGY, 1752 N ST NW, WASHINGTON, DC 20036-2904 USA. URL: http://www.asmusa.org IS - 0099-2240 MH - Rhodobacter-capsulatus MH - Burkholderia-cepacia MH - Nucleotide-sequence MH - Genetic-analysis MH - Catabolic genes MH - Yanoikuyae b1 MH - Degradation MH - Pyrene MH - Biodegradation MH - Phenanthrene. AB - In this study, the enzymes involved in polycyclic aromatic hydrocarbon (PAH) degradation in the chrysene-degrading organism Sphingomonas sp. strain CRY-1 were investigated. [C-14]chrysene mineralization experiments showed that PAH-grown bacteria produced high levels of chrysene-catabolic activity. One PAH-induced protein displayed similarity with a ring-hydroxylating dioxygenase beta subunit, and a second PAH-induced protein displayed similarity with an extradiol dioxygenase. The genes encoding these proteins were cloned, and sequence analysis revealed two distinct loci containing clustered catabolic genes with strong similarities to corresponding genes found in Novosphingobium aromaticivorans F199. In the first locus, two genes potentially encoding a terminal dioxygenase component, designated PhnI, were followed by a gene coding for an aryl alcohol dehydrogenase (phnB). The second locus contained five genes encoding an extradiol dioxygenase (phnC), a ferredoxin (phnA3), another oxygenase component (PhnII), and an isomerase (phnD). PhnI was found to be capable of converting several PAHs, including chrysene, to the corresponding dihydrodiols. The activity of PhnI was greatly enhanced upon coexpression of genes encoding a ferredoxin (phnA3) and a reductase (phnA4). Disruption of the phnA1(a) gene encoding the PhnI alpha subunit resulted in a mutant strain that had lost the ability to grow on PAHs. The recombinant PhnII enzyme overproduced in Escherichia coli functioned as a salicylate 1-hydroxylase. PhnII also used methylsalicylates and anthranilate as substrates. Our results indicated that a single enzyme (PhnI) was responsible for the initial attack of a range of PAHs, including chrysene, in strain CRY-1. Furthermore, the conversion of salicylate to catechol was catalyzed by a three-component oxygenase unrelated to known sallicylate hydroxylases. [References: 48] LG - English PT - Article SB - Current Contents(R)/Agriculture, Biology & Environmental Sciences Current Contents(R)/Life Sciences CC - Biology in Current Contents(R)/Agricultural, Biology & Environmental Sciences. Microbiology in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Jouanneau Y CEA, DRDC, BBSI, Lab Chim Prot F-38054 Grenoble 9 France CEA, DRDC, BBSI, Lab Chim Prot F-38054 Grenoble 9 France Univ Grenoble 1, UMR5092, CNRS, CEA,Lab Biochim & Biophys Syst Integres F-38041 Grenoble France <59> UI - 870GK-0008 DD - ISI Document Solution: 870GK AU - Saada A AU - Bar-Meir M AU - Belaiche C AU - Miller C AU - Elpeleg O MA - saada@szmc.org.il RA - Saada A TI - Evaluation of enzymatic assays and compounds affecting ATP production in mitochondrial respiratory chain complex I deficiency SO - Analytical Biochemistry. 335(1):66-72, 2004 Dec 1. AS - Anal. Biochem 2004 Dec 1;335(1):66-72 PU - ACADEMIC PRESS INC ELSEVIER SCIENCE, 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA. URL: http://www.apnet.com IS - 0003-2697 MH - Mitochondrial MH - Respiratory chain MH - Complex i MH - Atp production MH - Coenzyme q MH - Nadh-ferricyanide reductase MH - Nadh-ubiquinone reductase MH - Nadh-cytochrome c reductase MH - Riboflavin MH - Uridine MH - Carnitine MH - Lipoic acid. MH - Hereditary optic neuropathy MH - Ubiquinone oxidoreductase MH - Cofactor treatment MH - Lactic-acidosis MH - Free-radicals MH - Mutations MH - Nuclear MH - Nadh MH - Dehydrogenase MH - Disorders. AB - Isolated complex I deficiency is the most common oxidative phosphorylation defect and is associated with substantial morbidity and mortality. The diagnosis is made by enzymatic analysis and for most patients the molecular pathology remains undefined. Various cofactors and vitamins are frequently administered, but their efficacy have been difficult to assess. We employed determination of ATP production in fibroblast cell lines from patients with complex I deficiency to evaluate the usefulness of therapeutic agents. The effect of each additive varied among the different patients with certain agents favorably affecting ATP production rate in some of the patients and adversely affecting it in others. The reduced nicotinamide adenine dinucleotide (NADH)-ferricyanide reductase assay in muscle mitochondria correlated better than the NADH-coenzyme Q and NADH-cytochrome c assays with ATP production rate in fibroblasts. Our results underscore the necessity for evaluation of different agents for each patient separately. The NADH-ferricyanide reductase assay play a helpful role in directing mutation analysis and identifying patients which are more likely to have their cells amenable for ATP production assessment. (C) 2004 Elsevier Inc. All rights reserved. [References: 41] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Biochemistry & Biophysics in Current Contents(R)/Life Sciences. EW - 2005 week 01 IN - Reprint available from: Saada A Shaare Zedek Med Ctr, Metab Dis Unit POB 3235 IL-91031 Jerusalem Israel Shaare Zedek Med Ctr, Metab Dis Unit IL-91031 Jerusalem Israel Hebrew Univ Jerusalem, Fac Med Jerusalem Israel --_OVID_emlbndry_WKHLTH--