<1> UI - 842NH-0007 DD - ISI Document Solution: 842NH AU - Kramer DM AU - Avenson TJ AU - Edwards GE MA - dkramer@wsu.edu RA - Kramer DM TI - Dynamic flexibility in the light reactions of photosynthesis governed by both electron and proton reactions [Review] SO - Trends in Plant Science. 9(7):349-357, 2004 Jul. AS - Trends Plant Sci 2004 Jul;9(7):349-357 PU - ELSEVIER SCIENCE LONDON, 84 THEOBALDS RD, LONDON WC1X 8RR, ENGLAND. URL: http://www.epress.co.uk/ IS - 1360-1385 MH - Cytochrome b(6)f complex MH - Chloroplastic nad(p)h dehydrogenase MH - Nadh-specific dehydrogenase MH - Plastid ndh genes MH - Photosystem-i MH - Nad(p)h-plastoquinone oxidoreductase MH - Chlamydomonas-reinhardtii MH - Plastoquinone pool MH - Barley thylakoids MH - State transitions. AB - Plant photosynthesis performs the remarkable feat of converting light energy into usable chemical forms, which involves taming highly reactive intermediates without harming plant cells. This requires an apparatus that is not only efficient and robust but also flexible in its responses to changing environmental conditions. It also requires that the output of the energy-storing reactions be matched with the demands of metabolism. This article addresses the mechanisms by which this flexibility is achieved for short-term environmental changes. We argue that chloroplasts; need two types of flexible mechanisms: one for modulating the output ratio of ATP:NADPH, which involves cyclic electron flux around photosystem 1; and another for changing the regulatory sensitivity of the light-harvesting antenna to electron (and proton) flow. [References: 80] LG - English PT - Review 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 - 2004 week 36 IN - Reprint available from: Kramer DM Washington State Univ, Inst Biol Chem Pullman, WA 99164 USA Washington State Univ, Inst Biol Chem Pullman, WA 99164 USA Washington State Univ, Sch Biol Sci Pullman, WA 99164 USA <2> UI - 842HU-0007 DD - ISI Document Solution: 842HU AU - Nedelcu AM AU - Marcu O AU - Michod RE MA - anedelcu@unb.ca RA - Nedelcu AM TI - Sex as a response to oxidative stress: a twofold increase in cellular reactive oxygen species activates sex genes SO - Proceedings of the Royal Society of London - Series B: Biological Sciences. 271(1548):1591-1596, 2004 Aug 7. AS - Proc. R. Soc. Lond. Ser. B-Biol. Sci 2004 Aug 7;271(1548):1591-1596 PU - ROYAL SOC LONDON, 6 CARLTON HOUSE TERRACE, LONDON SW1Y 5AG, ENGLAND. URL: http://www.pubs.royalsoc.ac.uk IS - 0962-8452 MH - Oxidative stress MH - Reactive oxygen species MH - Facultatively sexual species MH - Sexual induction MH - Volvox carteri. MH - Hydrogen-peroxide MH - Volvox MH - Antioxidants MH - Pheromone MH - Alignment MH - Evolution MH - Mutation MH - Damage MH - Cells MH - Death. AB - Organisms are constantly subjected to factors that can alter the cellular redox balance and result in the formation of a series of highly reactive molecules known as reactive oxygen species (ROS). As ROS can be damaging to biological structures, cells evolved a series of mechanisms (e.g. cell-cycle arrest, programmed cell death) to respond to high levels of ROS (i.e. oxidative stress). Recently, we presented evidence that in a facultatively sexual lineage-the multicellular green alga Volvox carteri-sex is an additional response to increased levels of stress, and probably ROS and DNA damage. Here we show that, in V. carteri, (i) sex is triggered by an approximately twofold increase in the level of cellular ROS (induced either by the natural sex-inducing stress, namely heat, or by blocking the mitochondrial electron transport chain with antimycin A), and (ii) ROS are responsible for the activation of sex genes. As most types of stress result in the overproduction of ROS, we believe that our findings will prove to extend to other facultatively sexual lineages, which could be indicative of the ancestral role of sex as an adaptive response to stress and ROS-induced DNA damage. [References: 26] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Experimental Biology in Current Contents(R)/Life Sciences. EW - 2004 week 36 IN - Reprint available from: Nedelcu AM Univ New Brunswick, Dept Biol Fredericton NB E3B 6E1 Canada Univ New Brunswick, Dept Biol Fredericton NB E3B 6E1 Canada Univ Calif Irvine, Dept Dev & Cell Biol Irvine, CA 92697 USA Univ Arizona, Dept Ecol & Evolut Biol Tucson, AZ 85721 USA <3> UI - 842JM-0015 DD - ISI Document Solution: 842JM AU - Leggate EJ AU - Bill E AU - Essigke T AU - Ullmann GM AU - Hirst J MA - jh@mrc-dunn.cam.ac.uk RA - Hirst J TI - Formation and characterization of an all-ferrous Rieske cluster and stabilization of the [2Fe-2S](0) core by protonation SO - Proceedings of the National Academy of Sciences of the United States of America. 101(30):10913-10918, 2004 Jul 27. AS - Proc. Natl. Acad. Sci. U. S. A 2004 Jul 27;101(30):10913-10918 PU - NATL ACAD SCIENCES, 2101 CONSTITUTION AVE NW, WASHINGTON, DC 20418 USA. URL: http://www4.nationalacademies.org/nas/nashome.nsf IS - 0027-8424 MH - Iron-sulfur protein MH - Vinelandii ferredoxin-i MH - Azotobacter-vinelandii MH - 3fe-4s cluster MH - 2fe-2s cluster MH - Magnetic-susceptibility MH - Thermus-thermophilus MH - Film voltammetry MH - Redox properties MH - Fe4s4 cluster. AB - The all-ferrous Rieske cluster, [2Fe-2S](0), has been produced in solution and characterized by protein-film voltammetry and UV-visible, EPR, and Mossbauer spectroscopies. The [2Fe-2S]() cluster, in the overexpressed soluble domain of the Rieske protein from the bovine cytochrome bc(1), complex, is formed at -0.73 V at pH 7. Therefore, at pH 7, the [2Fe-2S](1+/0) couple is 1.0 V below the [2Fe-2S](2+/1+) couple. The two cluster-bound ferrous irons are both high spin(S 2), and they are coupled antiferromagnetically (-J greater than or equal to 30 cm(-1), H -2JS1(.)S2) to give a diamagnetic (S = 0) ground state. The ability of the Rieske cluster to exist in three oxidation states (2+, 1+, and 0) without an accompanying coupled reaction, such as a conformational change or protonation, is highly unusual. However, uncoupled reduction to the [2Fe-2S](0) state occurs at pH > 9.8 only, and at high pH the intact cluster persists in solution for < 1 min. At pH < 9.8, the all-ferrous cluster is stabilized significantly by protonation. A combination of experimental data and calculations based on density functional theory suggests strongly that the proton binds to one of the cluster mu2-sulfides, consistent with observations that reduced [3Fe-4S] clusters are protonated also. The implications for our understanding of coupled reactions at iron-sulfur clusters and of the factors that determine the relative stabilities of their different oxidation states are discussed. [References: 37] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Multidisciplinary in Current Contents(R)/Life Sciences. EW - 2004 week 36 IN - Reprint available from: Hirst J MRC, Dunn Human Nutr Unit Wellcome Trust Med Res Council Bldg,Hills Rd Cambridge CB2 2XY England MRC, Dunn Human Nutr Unit Cambridge CB2 2XY England Max Planck Inst Bioanorgan Chem D-45413 Mulheim Germany Univ Bayreuth D-95447 Bayreuth Germany <4> UI - 842JM-0031 DD - ISI Document Solution: 842JM AU - Millard A AU - Clokie MRJ AU - Shub DA AU - Mann NH MA - n.h.mann@warwick.ac.uk RA - Mann NH TI - Genetic organization of the psbAD region in phages infecting marine Synechococcus strains SO - Proceedings of the National Academy of Sciences of the United States of America. 101(30):11007-11012, 2004 Jul 27. AS - Proc. Natl. Acad. Sci. U. S. A 2004 Jul 27;101(30):11007-11012 PU - NATL ACAD SCIENCES, 2101 CONSTITUTION AVE NW, WASHINGTON, DC 20418 USA. URL: http://www4.nationalacademies.org/nas/nashome.nsf IS - 0027-8424 MH - Group-i introns MH - Open reading frames MH - Phytoplankton biomass MH - Marker exclusion MH - Genomic sequence MH - Picophytoplankton MH - Endonucleases MH - Cyanobacteria MH - Proteins MH - Growth. AB - The discovery of the genes psbA and psbD, encoding the D1 and D2 core components of the photosynthetic reaction center PSII (photosystem II), in the genome of the bacteriophage S-PM2 (a cyanomyovirus) that infects marine cyanobacteria begs the question as to how these genes were acquired. In an attempt to answer this question, it was established that the occurrence of the genes is widespread among marine cyanomyovirus isolates and may even extend to podoviruses. The phage psbA genes fall into a clade that includes the psbA genes from their potential Synechococcus and Prochlorococcus hosts, and thus, this phylogenetic analysis provides evidence to support the idea of the acquisition of these genes by horizontal gene transfer from their cyanobacterial hosts. However, the phage psbA genes form distinct subclades within this lineage, which suggests that their acquisition was not very recent. The psbA genes of two phages contain identical 212-bp insertions that exhibit all of the canonical structural features of a group I self-splicing intron. The different patterns of genetic organization of the psbAD region are consistent with the idea that the psbA and psbD genes were acquired more than once by cyanomyoviruses and that their horizontal transfer between phages via a common phage gene pool, as part of mobile genetic modules, may be a continuing process. In addition, genes were discovered encoding a high-light inducible protein and a putative key enzyme of dark metabolism, transaldolase, extending the areas of host-cell metabolism that may be affected by phage infection. [References: 49] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Multidisciplinary in Current Contents(R)/Life Sciences. EW - 2004 week 36 IN - Reprint available from: Mann NH Univ Warwick, Dept Biol Sci Coventry CV4 7AL W Midlands England Univ Warwick, Dept Biol Sci Coventry CV4 7AL W Midlands England SUNY Albany, Dept Biol Sci Albany, NY 12222 USA <5> UI - 842JM-0032 DD - ISI Document Solution: 842JM AU - Lindell D AU - Sullivan MB AU - Johnson ZI AU - Tolonen AC AU - Rohwer F AU - Chisholm SW MA - chisholm@mit.edu RA - Chisholm SW TI - Transfer of photosynthesis genes to and from Prochlorococcus viruses SO - Proceedings of the National Academy of Sciences of the United States of America. 101(30):11013-11018, 2004 Jul 27. AS - Proc. Natl. Acad. Sci. U. S. A 2004 Jul 27;101(30):11013-11018 PU - NATL ACAD SCIENCES, 2101 CONSTITUTION AVE NW, WASHINGTON, DC 20418 USA. URL: http://www4.nationalacademies.org/nas/nashome.nsf IS - 0027-8424 MH - Cyanobacterium prochlorococcus MH - Marine picophytoplankton MH - Synechococcus-cedrorum MH - Comparative genomics MH - Cyanophage as-1m MH - High-light MH - Sequence MH - Evolution MH - Phages MH - Dna. AB - Comparative genomics gives us a new window into phage-host interactions and their evolutionary implications. Here we report the presence of genes central to oxygenic photosynthesis in the genomes of three phages from two viral families (Myoviridae and Podoviridae) that infect the marine cyanobacterium Prochlorococcus. The genes that encode the photosystem II core reaction center protein D1 (psbA), and a high-light-inducible protein (HLIP) (hli) are present in all three genomes. Both myoviruses contain additional hli gene types, and one of them encodes the second photosystem II core reaction center protein D2 (psbD), whereas the other encodes the photosynthetic electron transport proteins plastocyanin (petE) and ferredoxin (petF). These uninterrupted, full-length genes are conserved in their amino acid sequence, suggesting that they encode functional proteins that may help maintain photosynthetic activity during infection. Phylogenetic analyses show that phage D1, D2, and HLIP proteins cluster with those from Prochlorococcus, indicating that they are of cyanobacterial origin. Their distribution among several Prochlorococcus clades further suggests that the genes encoding these proteins were transferred from host to phage multiple times. Phage HLIPs cluster with multicopy types found exclusively in Prochlorocococus, suggesting that phage may be mediating the expansion of the hli gene family by transferring these genes back to their hosts after a period of evolution in the phage. These gene transfers are likely to play a role in the fitness landscape of hosts and phages in the surface oceans. [References: 48] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Multidisciplinary in Current Contents(R)/Life Sciences. EW - 2004 week 36 IN - Reprint available from: Chisholm SW MIT, Dept Civil & Environm Engn Room 48-425,77 Massachusetts Ave Cambridge, MA 02139 USA MIT, Dept Civil & Environm Engn Cambridge, MA 02139 USA MIT, Dept Biol Cambridge, MA 02139 USA MIT, Woods Hole Oceanog Inst, Program Biol Oceanog Cambridge, MA 02139 USA MIT Cambridge, MA USA San Diego State Univ, Dept Biol San Diego, CA 92182 USA <6> UI - 842LP-0012 DD - ISI Document Solution: 842LP AU - Calatayud A AU - Barreno E MA - angeles.calatayud@uv.es RA - Calatayud A TI - Response to ozone in two lettuce varieties on chlorophyll a fluorescence, photosynthetic pigments and lipid peroxidation SO - Plant Physiology & Biochemistry. 42(6):549-555, 2004 Jun. AS - Plant Physiol. Biochem 2004 Jun;42(6):549-555 PU - EDITIONS SCIENTIFIQUES MEDICALES ELSEVIER, 23 RUE LINOIS, 75724 PARIS, FRANCE. URL: http://www.elsevier.nl IS - 0981-9428 MH - Carotenoids MH - Chlorophyll fluorescence MH - Lettuce MH - Lipid peroxidation MH - Photosynthetic pigments MH - Ozone. MH - Open-top chambers MH - Quantum yield MH - Antioxidant systems MH - Spinach leaves MH - Term exposure MH - Sativa l MH - Sensitivity MH - Fumigation MH - Photoinhibition MH - Chloroplasts. AB - The effect of different O-3 concentrations on two lettuce (Lactuca sativa L.) varieties (Valladolid and Morelia) was investigated through chlorophyll (Chi) a fluorescence parameters, photosynthetic pigments (Chi a, b and total carotenoid), lipid peroxidation and crop yield. Ozone fumigation caused: a decrease in maximum quantum yield of photosystem II (PSII) photochemistry (F-v/F-m) in mature leaves, a reduction in the non-cyclic electron flow (phi(PSII)) and a lower capacity to reoxidize the Q(A) Pool (q(P)). These reductions were significant in the Valladolid var. but not in the Morelia var. A significant decrease in Chi a, b and in the total carotenoids was observed in the Valladolid var. but not in the Morelia var. mainly under O-3 fumigation conditions. We observed that the NPQ parameter did not increase in parallel to the q(P) reduction seen in the Valladolid var. O-3 fumigation with respect to air charcoal filtered air conditions. This fact could be associated with a lower capacity for dissipation of non-radiative excess energy and it may be closely correlated with significant decreases in photosynthetic pigment concentration. A decrease in NPQ from air ozone-free to ozone fumigation in the Morelia var. can be explained by the need to maintain the photochemical quenching under O-3 stress. It may also be associated with a slight increase in photosynthetic pigments. The differences between the two varieties may indicate that the Valladolid var. is more susceptible to O-3 damage. (C) 2004 Elsevier SAS. All rights reserved. [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 - 2004 week 36 IN - Reprint available from: Calatayud A Univ Valencia, Fac Ciencias Biol, Dept Biol Vegetal C Dr Moliner 50 Valencia 46100 Spain Univ Valencia, Fac Ciencias Biol, Dept Biol Vegetal Valencia 46100 Spain <7> UI - 842LP-0013 DD - ISI Document Solution: 842LP AU - Olsson U AU - Sirijovski N AU - Hansson M MA - mats.hansson@biokem.lu.se RA - Hansson M TI - Characterization of eight barley xantha-f mutants deficient in magnesium chelatase SO - Plant Physiology & Biochemistry. 42(6):557-564, 2004 Jun. AS - Plant Physiol. Biochem 2004 Jun;42(6):557-564 PU - EDITIONS SCIENTIFIQUES MEDICALES ELSEVIER, 23 RUE LINOIS, 75724 PARIS, FRANCE. URL: http://www.elsevier.nl IS - 0981-9428 MH - Bchh MH - Chlh MH - Hordeum vulgare MH - Mg-chelatase MH - Mutation MH - Protoporphyrin ix. MH - Nonsense-mediated decay MH - Mg-chelatase MH - Protoporphyrin-ix MH - Messenger-rna MH - H-subunit MH - Rhodobacter-sphaeroides MH - Arabidopsis-thaliana MH - Porphyrin metalation MH - Atpase activity MH - Gene. AB - Magnesium chelatase (EC 6.6.1.1) catalyses the insertion of magnesium into protoporphyrin IX, the first unique step of the chlorophyll biosynthetic pathway. The enzyme is composed of three different subunits of approximately 40, 70 and 140 kDa. In barley (Hordeum vulgare L.) the subunits are encoded by the genes Xantha-h, Xantha-g and Xantha-f. In the 1950s, eight induced xantha-f mutants were isolated. In this work we characterized these mutations at the DNA level and provided explanations for their phenotypes. The xantha-f(10) mutation is a 3 bp deletion, resulting in a polypeptide lacking the glutamate residue at position 424. The leaky mutation xantha-f(26) has a missense mutation leading to a M632R exchange. The xantha-f(27) and -f(40) are deletions of 14 and 2 bp, respectively, resulting in truncated polypeptides of 1104 and 899 amino acid residues, respectively. Mutation xantha-f(41) is an in-frame deletion that removes A439, L440, Q441 and V442 from the resulting protein. Mutation xantha-f(58) is most likely a deletion of the whole Xantha-f gene, as no DNA fragments could be detected by PCR or southern blot experiments. The slightly leaky xantha-f(60) and non-leaky -f(68) mutations each have a missense mutation causing a P393L and G794E exchange in the polypeptide, respectively. (C) 2004 Elsevier SAS. All rights reserved. [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 - 2004 week 36 IN - Reprint available from: Hansson M Lund Univ, Dept Biochem Box 124 S-22100 Lund Sweden Lund Univ, Dept Biochem S-22100 Lund Sweden <8> UI - 842OM-0014 DD - ISI Document Solution: 842OM AU - Hitchcock GL AU - Chen RF AU - Gardner GB AU - Wiseman WJ MA - g.hitchcock@miami.edu RA - Hitchcock GL TI - A Lagrangian view of fluorescent chromophoric dissolved organic matter distributions in the Mississippi River plume SO - Marine Chemistry. 89(1-4):225-239, 2004 Oct. AS - Mar. Chem 2004 Oct;89(1-4):225-239 PU - ELSEVIER SCIENCE BV, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS. URL: http://www.elsevier.nl IS - 0304-4203 MH - Lagrangian study MH - Chromophoric dissolved organic matter MH - Mississippi river plume. MH - Louisiana coastal current MH - In-situ MH - Salinity variability MH - Optical-absorption MH - Continental-shelf MH - Transition zone MH - St-lawrence MH - North-sea MH - Waters MH - Chlorophyll. AB - In April 2001, three instrumented surface drifters were deployed in the Mississippi River plume near the mouth of Southwest Pass. The plume was characterized by strong surface gradients of salinity, temperature, and chromophoric dissolved organic matter fluorescence (F-CDOM). The drifters initially headed west and attained peak speeds of 1 m s(-1) within 5 h after release. Thereafter, velocity decreased as the triad headed north in the Louisiana Bight. Linear relationships between F-CDOM and salinity identified two subsurface sources of high salinity water (salinity >35) underlying the surface plume. The platforms stalled in a surface front about 40 h after deployment, and then slowly drifted south along the eastern perimeter of the plume. Shoreward of the plume front there were patches of low-salinity, high F-CDOM 'patches' of surface waters that likely originated in the marshes, bayous, and other smaller distributaries of the delta. (C) 2004 Published by Elsevier B.V. [References: 45] LG - English PT - Article SB - Current Contents(R)/Agriculture, Biology & Environmental Sciences Current Contents(R)/Physical, Chemical & Earth Sciences CC - Aquatic Sciences in Current Contents(R)/Agricultural, Biology & Environmental Sciences. Earth Sciences in Current Contents(R)/Physical, Chemical & Earth Sciences. EW - 2004 week 36 IN - Reprint available from: Hitchcock GL Univ Miami, Rosenstiel Sch Marine & Atmospher Sci 4600 Rickenbacker Causeway Miami, FL 33149 USA Univ Miami, Rosenstiel Sch Marine & Atmospher Sci Miami, FL 33149 USA Univ Massachusetts, Dept Environm Coastal & Ocean Sci Boston, MA 02125 USA Louisiana State Univ, Inst Coastal Studies Baton Rouge, LA 70803 USA <9> UI - 842OM-0016 DD - ISI Document Solution: 842OM AU - Chen RF AU - Bissett P AU - Coble P AU - Conmy R AU - Gardner GB AU - Moran MA AU - Wang XC AU - Wells ML AU - Whelan P AU - Zepp RG MA - bob.chem@umb.edu RA - Chen RF TI - Chromophoric dissolved organic matter (CDOM) source characterization in the Louisiana Bight SO - Marine Chemistry. 89(1-4):257-272, 2004 Oct. AS - Mar. Chem 2004 Oct;89(1-4):257-272 PU - ELSEVIER SCIENCE BV, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS. URL: http://www.elsevier.nl IS - 0304-4203 MH - Chromophoric dissolved organic matter MH - Source characterization MH - Louisiana bight. MH - Mid-atlantic bight MH - Vertical-distribution MH - Optical-properties MH - Humic substances MH - Solar-radiation MH - Natural-waters MH - Coastal waters MH - In-situ MH - Carbon MH - Fluorescence. AB - Chromophoric dissolved organic matter (CDOM) in the Mississippi plume region may have several distinct sources: riverine (terrestrial soils), wetland (terrestrial plants), biological production (phytoplankton, zooplankton, microbial), and sediments. Complex mixing, photodegradation, and biological processes make differentiation of the specific sources of CDOM difficult. Using a combination of high resolution in situ observations on an undulating vehicle, the ECOShuttle, a pumping system mounted on the vehicle, and detailed chemical and biological analyses of discrete samples allowed us to characterize two specific sources of CDOM in the Louisiana Bight: the river water constrained in the upper 12 m of the Mississippi River plume and several subsurface layers of CDOM below the plume. The subsurface CDOM maxima were coincident with steep pycnoclines and sometimes with maxima in chlorophyll a fluorescence. Both sources were actively supplying CDOM to the same location by entirely different processes. The subsurface CDOM was more biologically labile and photochemically refractory than the surface CDOM. Optical properties were also different with a relatively higher protein fluorescence and a lower spectral slope coefficient in the subsurface CDOM. The geographical extent of the two sources was determined by three-dimensional mapping of the area, and due to the relatively calm conditions in the summer of 2000, thin layers of CDOM produced in the subsurface were observed throughout the region. While riverine inputs dominated the distribution of CDOM in surface waters <12 m in depth, biological production of CDOM, probably due to the bacterial degradation of phytoplankton produced DOM dominated the subsurface waters. (C) 2004 Elsevier B.V. All rights reserved. [References: 49] LG - English PT - Article SB - Current Contents(R)/Agriculture, Biology & Environmental Sciences Current Contents(R)/Physical, Chemical & Earth Sciences CC - Aquatic Sciences in Current Contents(R)/Agricultural, Biology & Environmental Sciences. Earth Sciences in Current Contents(R)/Physical, Chemical & Earth Sciences. EW - 2004 week 36 IN - Reprint available from: Chen RF Univ Massachusetts 100 Morrissey Blvd Boston, MA 02125 USA Univ Massachusetts Boston, MA 02125 USA Florida Environm Res Inst Tampa, FL 33611 USA Univ S Florida, Coll Marine Sci St Petersburg, FL 33701 USA Univ Georgia, Dept Marine Sci Athens, GA 30602 USA Univ Maine, Sch Marine Sci Orono, ME 04469 USA US EPA Athens, GA 30605 USA <10> UI - 841UC-0005 DD - ISI Document Solution: 841UC AU - Prosek M AU - Smidovnik A AU - Fir M AU - Strazisar M RA - Prosek M TI - TLC identification and quantification of coenzyme Q10-beta-cyclodextrin complex SO - JPC-Journal of Planar Chromatography-Modern Tlc. 17(3):181-185, 2004 May-Jun. AS - JPC-J. Planar Chromatogr.-Mod. TLC 2004 May-Jun;17(3):181-185 PU - RESEARCH INST MEDICINAL PLANTS, PO BOX 11, H-2011 BUDAKALASZ, HUNGARY IS - 0933-4173 MH - Tlc MH - Two-dimensional tlc MH - Multidimensional tlc MH - Coq10 MH - Ubiquinone MH - Beta-cyclodextrin complex. MH - Q(10) MH - Uncertainty. AB - TLC is often set aside as a result of unjustified simplification of analytical knowledge and, at the same time, over-emphasis of the use of metrological solutions. Some analysts assume that techniques with smaller measurement uncertainty automatically improve the reliability of their analytical results. This is not true. The reliability of some TLC techniques is demonstrated by analysis of an inclusion complex of coenzyme Q10 (CoQ10) with beta-cyclodextrin, which was prepared because it is a water-soluble food additive. The products obtained were analyzed by one-dimensional, two-dimensional, and multi-dimensional TLC (according to Ebel). These inexpensive, rapid, and very informative methods were used in-line during the preparation steps. Separation was performed in two steps, with dioxane-water, 50 + 50 (v/v), as the first mobile phase and chloroform-methanol, 55 + 45 (v/v), as the second. The development distance was 7.5 cm. The separated spots were visualized in two steps, first with 5% phosphomolybdic acid in EtOH and drying at 110degreesC, then with 50% H2SO4 and heating at 120degreesC for 5 min. After the first treatment blue spots on yellow background were observed for CoQ10. After spraying with H2SO4 dark blue spots of CoQ10 were observed on a light blue background. Images were acquired with a scanner and quantification was performed by use of TLC software. The synthetic yield was calculated from the concentrations determined. The results obtained were later confirmed by use of IR, NMR, and HPLC-MS. [References: 17] LG - English PT - Article SB - Current Contents(R)/Physical, Chemical & Earth Sciences CC - Spectroscopy/Instrumentation/Analytical Sciences in Current Contents(R)/Physical, Chemical & Earth Sciences. EW - 2004 week 36 IN - Reprint available from: Prosek M Natl Inst Chem Hajdrihova 19 Ljubljana 1000 Slovenia Natl Inst Chem Ljubljana 1000 Slovenia <11> UI - 841JN-0001 DD - ISI Document Solution: 841JN AU - Mouget JL AU - Rosa P AU - Tremblin G MA - jlmouget@univ-lemans.fr RA - Mouget JL TI - Acclimation of Haslea ostrearia to light of different spectral qualities - confirmation of 'chromatic adaptation' in diatoms SO - Journal of Photochemistry & Photobiology. B - Biology. 75(1-2):1-11, 2004 Jul 19. AS - J. Photochem. Photobiol. B-Biol 2004 Jul 19;75(1-2):1-11 PU - ELSEVIER SCIENCE SA, PO BOX 564, 1001 LAUSANNE, SWITZERLAND. URL: http://www.elsevier.nl IS - 1011-1344 MH - Chlorophyll fluorescence MH - Chromatic acclimation MH - Diatom MH - Haslea ostrearia MH - Photosynthetic pigments. MH - Blue-green light MH - Unicellular marine-algae MH - Skeletonema-costatum MH - Photosynthetic pigments MH - Heterocapsa-pygmaea MH - Carbon fixation MH - Quantum yield MH - Chloroplast structure MH - Chemical-composition MH - Oxygen evolution. AB - The marine diatom Haslea ostrearia was cultured under light of different qualities, white (WL), blue (BL), green (GL), yellow (YL), red (RL), and far-red (FRL) and at two irradiance levels, low and high (20 and 100 mumol photons m(-2) s(-1), respectively). The effects of the different light regimes were studied on growth, pigment content, and photosynthesis, estimated by the modulated fluorescence of chlorophyll, as relative electron transport rate (rETR). For all the light qualities studied, growth rates were higher at high irradiance. Compared to the corresponding WL controls, growth was higher in BL and lower in YL at low irradiance, and lower in YL and GL at high irradiance. Except for YL, almost all the pigment contents of the cells were lower at high irradiance. At low irradiance, cell pigment contents (chlorophyll a and c, fucoxanthin) and pigment ratios (in function of chlorophyll a) were lower in YL, RL, and FRL. Whatever the irradiance level, the maximum PSII quantum efficiency (F-v/F-m) remained almost constant for WL, BL, and GL. Other fluorescence parameters (photochemical quenching, rETR(max), and alpha, the maximum light utilization coefficient) were lower in GL, YL, RL, and FRL, at low irradiance. Although not statistically significant, BL caused an increase in these fluorescence parameters. These findings are interpreted as evidence that inverse chromatic acclimation occurs in diatoms. (C) 2004 Elsevier B.V. All rights reserved. [References: 48] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Biochemistry & Biophysics in Current Contents(R)/Life Sciences. EW - 2004 week 36 IN - Reprint available from: Mouget JL Univ Maine, Fac Sci & Tech, Lab Physiol & Biochim Vegetales, EA 2663,ISOMer Av O Messiaen F-72085 Le Mans 9 France Univ Maine, Fac Sci & Tech, Lab Physiol & Biochim Vegetales, EA 2663,ISOMer F-72085 Le Mans 9 France Univ Nantes, Biol Marine Lab, EA 2663, ISOMer F-44322 Nantes France <12> UI - 841JN-0006 DD - ISI Document Solution: 841JN AU - Stroch M AU - Cajanek M AU - Kalina J AU - Spunda V MA - Vladimir.Spunda@osu.cz RA - Spunda V TI - Regulation of the excitation energy utilization in the photosynthetic apparatus of chlorina f2 barley mutant grown under different irradiances SO - Journal of Photochemistry & Photobiology. B - Biology. 75(1-2):41-50, 2004 Jul 19. AS - J. Photochem. Photobiol. B-Biol 2004 Jul 19;75(1-2):41-50 PU - ELSEVIER SCIENCE SA, PO BOX 564, 1001 LAUSANNE, SWITZERLAND. URL: http://www.elsevier.nl IS - 1011-1344 MH - Chlorina f2 MH - Chlorophyll fluorescence MH - Hordeum vulgare MH - Light acclimation MH - Non-photochemical quenching MH - Photoprotection. MH - Light-harvesting complex MH - Hordeum-vulgare l. MH - Chlorophyll-b-less MH - Femtosecond transient absorption MH - Xanthophyll-cycle MH - Photosystem-ii MH - Shade leaves MH - Antenna size MH - Wild-type MH - In-vivo. AB - Acclimation of the photosynthetic apparatus of chlorophyll b-less barley mutant chlorina f2 to low light (100 mumol m(-2) s(-1); LL) and extremely high light level (1000 mumol m(-2) s(-1); HL) was examined using techniques of pigment analysis and chlorophyll a fluorescence measurements at room temperature and at 77 K. The absence of chlorophyll b in LL-grown chlorina f2 resulted in the reduction of functional antenna size of both photosystem II (by 67%) and photosystem I (by 21%). Chlorophyll fluorescence characteristics of the LL-grown mutant indicated no impairment of the utilization of absorbed light energy in photosystem 11 photochemistry. Thermal dissipation of excitation energy estimated as non-photochemical quenching of minimal fluorescence (SV0) was significantly higher as compared to the wild-type barley grown under LL. Despite impaired assembly of pigment-protein complexes, chlorina f2 was able to efficiently acclimate to HL. In comparison with chlorina f2 grown under LL, HL-grown chlorina f2 was characterized by unaffected maximal photochemical efficiency of photosystem II (F-v/F-m), doubled content of both beta-carotene and the xanthophyll cycle pigments and considerably reduced efficiency of excitation energy transfer from carotenoids to chlorophyll a. The enormous xanthophyll cycle pool size was however associated with reduced SV0 capacity. We suggest that the substantial part of the xanthophyll cycle pigments is not bound to the remaining pigment-protein complexes and acts as filter for excitation energy, thereby contributing to the efficient photoprotection of chlorina f2 grown under HL. (C) 2004 Elsevier B.V. All rights reserved. [References: 52] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Biochemistry & Biophysics in Current Contents(R)/Life Sciences. EW - 2004 week 36 IN - Reprint available from: Spunda V Ostrava Univ, Fac Sci, Dept Phys 30 Dubna 22 Ostrava 70103 1 Czech Republic Ostrava Univ, Fac Sci, Dept Phys Ostrava 70103 1 Czech Republic Univ S Bohemia, Inst Biol Phys Ceske Budejovice 37005 Czech Republic <13> UI - 841JN-0010 DD - ISI Document Solution: 841JN AU - Marchand M AU - Dewez D AU - Franck F AU - Popovic R MA - popovic.radovan@uqam.ca RA - Popovic R TI - Protochlorophyllide phototransformation in the bundle sheath cells of Zea mays SO - Journal of Photochemistry & Photobiology. B - Biology. 75(1-2):73-80, 2004 Jul 19. AS - J. Photochem. Photobiol. B-Biol 2004 Jul 19;75(1-2):73-80 PU - ELSEVIER SCIENCE SA, PO BOX 564, 1001 LAUSANNE, SWITZERLAND. URL: http://www.elsevier.nl IS - 1011-1344 MH - Chlorophyll biosynthesis MH - C-4 plant MH - Photosystems assembly MH - Protochlorophyllide phototransformation MH - Zea mays. MH - Etiolated barley leaves MH - Greening bean-leaves MH - Photosystem-ii MH - Chlorophyll formation MH - Prolamellar bodies MH - Complexes MH - Dark MH - Mesophyll MH - Biosynthesis MH - Chloroplasts. AB - The protochlorophyllide transformation process was investigated by using comparative analysis of 77 K fluorescence spectral changes occurring in isolated bundle sheath (BS) cells of etiolated Zea mays leaves after being exposed to a 200 ms saturating flash. Deconvolution analysis of the fluorescence spectra showed essential differences in the ratio of protochlorophyll(ides) and chlorophyll(ides) spectral forms indicating for BS cells to have a characteristic pathway of protochlorophyllide transformation. Bundle sheath cells showed a high ratio between non-photoactive protochlorophyll(ide)-F632 and photoactive protochlorophyllide-F655. In those cells, the 200 ins flash triggered a preferential formation of chlorophyll(ide)-F675 which remained stable in the dark for at least 90 min. Isolated BS cells showed an accumulation of chlorophyll(ide)-F675 resulting in the formation of inactive photosystem II. However for mesophyll cells of intact leaves, it was found to have a high ratio between photoactive and non-photoactive protochlorophyll(ide), showing the succession of chlorophyll(ide) forms usually known in C-3 plants. Protochlorophyllide phototransformation pathway in BS cells related to early stages of plastid differentiation triggered by light may indicate specific conditions for PSII assembly process leading to inactive PSII forms. (C) 2004 Elsevier B.V. All rights reserved. [References: 34] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Biochemistry & Biophysics in Current Contents(R)/Life Sciences. EW - 2004 week 36 IN - Reprint available from: Popovic R Univ Quebec, Dept Chim & Biochim, TOXEN, Ctr Rech Toxicol Environm Case Postale 8888,Succursale Ctr Ville Montreal PQ H3C 3P8 Canada Univ Quebec, Dept Chim & Biochim, TOXEN, Ctr Rech Toxicol Environm Montreal PQ H3C 3P8 Canada Univ Liege, Inst Bot, Dept Sci Vie, Lab Biochim & Photobiol B-4000 Liege Belgium <14> UI - 842DC-0031 DD - ISI Document Solution: 842DC AU - Pushkar YN AU - Stehlik D AU - van Gastel M AU - Lubitz W MA - stehlik@physik.fu-berlin.de RA - Stehlik D TI - An EPR/ENDOR study of the asymmetric hydrogen bond between the quinone electron acceptor and the protein backbone in photosystem I SO - Journal of Molecular Structure. 700(1-3 Special Issue SI):233-241, 2004 Aug 20. AS - J. Mol. Struct 2004 Aug 20;700(1-3 Special Issue SI):233-241 PU - ELSEVIER SCIENCE BV, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS. URL: http://www.elsevier.nl IS - 0022-2860 MH - Hydrogen bond MH - Quinone radical anion MH - Photosystem i MH - Epr and endor spectroscopy MH - Hyperfine tensor. MH - Biosynthetic-pathway mutants MH - Paramagnetic-resonance spectroscopy MH - Photosynthetic reaction centers MH - Site-directed mutants MH - Endor spectroscopy MH - Foreign quinone MH - Anion-radicals MH - A(1) site MH - State p(700)(center-dot+)a(1)(center-dot-) MH - 35 ghz. AB - Hydrogen bonding to the photoaccumulated secondary acceptor radical anion A(1)(.-) in photosystem (PS) I has been studied using pulsed Q-band ENDOR spectroscopy. With deuterated quinone in protonated PS I particles it is demonstrated that the observed radical anion has only one hydrogen-bond hyperfine coupling (hfc) tensor with tensor components above the 2 MHz range. Below 2 MHz the protein matrix protons dominate and a second weak H-bond could not be detected. The spectral resolution of pulsed Q-band ENDOR is critically required to separate the signals of the H-bond proton from those of the primary chlorophyll acceptor, A(0)(.-), which cannot be avoided to be formed to some extent in the photoaccumulation procedure. The determined H-bond hfc tensor of A(1)(.-) is found to be close to axial symmetry with a small isotropic component, as expected from a predominantly dipolar electron-proton spin interaction in a hydrogen-bond. The principal tensor components are A(\\) = (+)7.7, MHz A(perpendicular to) = (-)4.9 MHz, A(iso) = (-)0.7 MHz. The magnitude of the dipolar tensor corresponds to an unusually short H-bond which can be estimated from the point-dipole approximation (similar to 1.5 +/- 0.1 Angstrom). Based on previous studies with A- and B-branch specific site-directed mutants of the A(1) site of PS I and the chosen photoaccumulation protocol, the observed A(1)(.-) radical anion can be assigned to the Q(K)-A site of the A-branch. The observed H-bond hfc tensor is compared to those determined for related quinone radical anions observed in frozen protic solution as well as in the Q(A) site of type II bacterial reaction centers. (C) 2004 Elsevier B.V. All rights reserved. [References: 41] 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 - 2004 week 36 IN - Reprint available from: Stehlik D Free Univ Berlin, Inst Expt Phys Arnimallee 14 D-14195 Berlin Germany Free Univ Berlin, Inst Expt Phys D-14195 Berlin Germany Max Planck Inst Bioanorgan Chem D-45470 Mulheim Germany <15> UI - 841JC-0023 DD - ISI Document Solution: 841JC AU - Esser L AU - Quinn B AU - Li YF AU - Zhang MQ AU - Elberry M AU - Yu L AU - Yu CA AU - Xia D MA - dixia@helix.nih.gov RA - Xia D TI - Crystallographic studies of quinol oxidation site inhibitors: A modified classification of inhibitors for the cytochrome bc(1) complex SO - Journal of Molecular Biology. 341(1):281-302, 2004 Jul 30. AS - J. Mol. Biol 2004 Jul 30;341(1):281-302 PU - ACADEMIC PRESS LTD ELSEVIER SCIENCE LTD, 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND. URL: http://www.apnet.com IS - 0022-2836 MH - Cytochrome bc(1) MH - Crystal structures MH - Inhibitors MH - Membrane protein MH - Electron transport. MH - Iron-sulfur protein MH - Mitochondrial respiratory-chain MH - Bovine heart-mitochondria MH - Protonmotive q-cycle MH - Electron-transfer MH - C reductase MH - Bc1 complex MH - Saccharomyces-cerevisiae MH - Rhodobacter-sphaeroides MH - Crystal-structure. AB - Cytochrome bc(1) is an integral membrane protein complex essential for cellular respiration and photosynthesis; it couples electron transfer from quinol to cytochrome c to proton translocation across the membrane. Specific bc(1), inhibitors have not only played crucial roles in elucidating the mechanism of bc(1) function but have also provided leads for the development of novel antibiotics. Crystal structures of bovine bc(1) in complex with the specific Q(o) site inhibitors azoxystrobin, MOAS, myxothiazol, stigmatellin and 5-undecyl-6-hydroxy-4,7-dioxobenzothiazole were determined. Interactions, conformational changes and possible mechanisms of resistance, specific to each inhibitor, were defined. Residues and secondary structure elements that are capable of discriminating different classes of Q(o) site inhibitors were identified for the cytochrome b subunit. Directions in the displacement of the cd1 helix of cytochrome b subunit in response to various Q(o) site inhibitors were correlated to the binary conformational switch of the extrinsic domain of the iron-sulfur protein subunit. The new structural information, together with structures previously determined, provide a basis that, combined with biophysical and mutational data, suggest a modification to the existing classification of bc(1) inhibitors. bc(1) inhibitors are grouped into three classes: class P inhibitors bind to the Q(o) site, class N inhibitors bind to the Q(i) site and the class PN inhibitors target both sites. Class P contains two subgroups, Pm and Pf, that are distinct by their ability to induce mobile or fixed conformation of iron-sulfur protein. Published by Elsevier Ltd. [References: 64] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Molecular Biology & Genetics in Current Contents(R)/Life Sciences. EW - 2004 week 36 IN - Reprint available from: Xia D NCI, Cell Biol Lab, Natl Inst Hlth Bethesda, MD 20892 USA NCI, Cell Biol Lab, Natl Inst Hlth Bethesda, MD 20892 USA Oklahoma State Univ, Dept Biochem & Mol Biol Stillwater, OK 74078 USA <16> UI - 842RK-0003 DD - ISI Document Solution: 842RK AU - Anthony JR AU - Newman JD AU - Donohue TJ MA - tdonohue@bact.wisc.edu RA - Donohue TJ TI - Interactions between the Rhodobacter sphaeroides ECF sigma factor, sigma(E), and its anti-sigma factor, ChrR SO - Journal of Molecular Biology. 341(2):345-360, 2004 Aug 6. AS - J. Mol. Biol 2004 Aug 6;341(2):345-360 PU - ACADEMIC PRESS LTD ELSEVIER SCIENCE LTD, 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND. URL: http://www.apnet.com IS - 0022-2836 MH - Sigma factor MH - Anti-sigma factor MH - Transcription MH - Regulation MH - Rhodobacter sphaeroides. MH - Coli rna-polymerase MH - Nickel resistance determinant MH - Cytochrome c(2) gene MH - Escherichia-coli MH - Streptomyces-coelicolor MH - Crystal-structure MH - Transcription initiation MH - Extracytoplasmic stress MH - Bacteriophage-t4 asia MH - Angstrom resolution. AB - Rhodobacter sphaeroides sigma(E) is a member of the extra cytoplasmic function sigma factor (ECF) family, whose members have been shown to regulate gene expression in response to a variety of signals. The functions of ECF family members are commonly regulated by a specific, reversible interaction with a cognate anti-sigma factor. In R. sphaeroides, sigma(E) activity is inhibited by ChrR, a member of a newly discovered family of zinc containing anti-sigma factors. We used gel filtration chromatography to gain insight into the mechanism by which ChrR inhibits sigma(E) activity We found that formation of the sigma(E):ChrR complex inhibits the ability of sigma(E) to form a stable complex with core RNA polymerase. Since the sigma(E):ChrR complex inhibits the ability of the sigma factor to bind RNA polymerase, we sought to identify amino acid substitutions in sigma(E) that altered the sensitivity of this sigma factor to inhibition by ChrR. This analysis identified single amino acid changes in conserved region 2.1 of sigma(E) that either increased or decreased the sensitivity of sigma(E) for inhibition by ChrR. Many of the amino acid residues that alter the sensitivity of sigma(E) to ChrR are located within regions known to be important for interacting with core RNA polymerase in other members of the sigma(70) superfamily. Our results suggest a model where solvent-exposed residues with region 2.1 of sigma(E) interact with ChrR to sterically occlude this sigma factor from binding core RNA polymerase and to inhibit target gene expression. (C) 2004 Elsevier Ltd. All rights reserved. [References: 61] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Molecular Biology & Genetics in Current Contents(R)/Life Sciences. EW - 2004 week 36 IN - Reprint available from: Donohue TJ Univ Wisconsin, Dept Bacteriol 420 Henry Mall Madison, WI 53706 USA Univ Wisconsin, Dept Bacteriol Madison, WI 53706 USA <17> UI - 842SR-0013 DD - ISI Document Solution: 842SR AU - Caraceni P AU - Bianchi C AU - Domenicali M AU - Pertosa AM AU - Maiolini E AU - Castelli GP AU - Nardo B AU - Trevisani F AU - Lenaz G AU - Bernardi M MA - caraceni@med.unibo.it RA - Caraceni P TI - Impairment of mitochondrial oxidative phosphorylation in rat fatty liver exposed to preservation-reperfusion injury SO - Journal of Hepatology. 41(1):82-88, 2004 Jul. AS - J. Hepatol 2004 Jul;41(1):82-88 PU - ELSEVIER SCIENCE BV, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS. URL: http://www.elsevier.nl IS - 0168-8278 MH - Liver preservation injury MH - Fatty liver MH - Mitochondria MH - Oxidative phosphorylation. MH - Cold preservation MH - Respiratory-function MH - Nutritional-status MH - Energy-metabolism MH - Steatotic graft MH - Transplantation MH - Viability MH - Ischemia MH - Necrosis MH - Stress. AB - Background/Aims: As the impairment of the cellular energy metabolism contributes to the failure of fatty liver grafts after transplantation, we aimed to determine whether steatosis affects the oxidative phosphorylation activity during preservation. Methods: Rat normal and fatty livers were preserved for 18 h and then reperfused with warm oxygenated solution. The oxidative phosphorylation, the F0F1-ATPase and the Complex I activities were assessed in isolated mitochondria before and after preservation, and during reperfusion. The ALT release and portal pressure were monitored during reperfusion. Results: The baseline phosphorylation activity was similar in normal and steatotic mitochondria. After cold preservation, the respiratory control index and state 3 respiration decreased significantly only in steatotic livers. Reperfusion induced a further deterioration in either group. Contrary to normal liver, uncoupling of fatty liver mitochondria allowed the recovery of the maximal respiration rate only using succinate (Complex II-dependent substrate), but not glutamate-malate (Complex I-dependent). Complex I dysfunction was confirmed spectrophotometrically. The ATPase activity was also significantly lower in fatty livers. Finally, ALT release and portal pressure were greater in steatotic livers. Conclusions: The alteration of the oxidative phosphorylation activity during preservation is greatly exacerbated by fatty infiltration likely resulting from damage of the respiratory chain Complex I and of the F0F1-ATP synthase. (C) 2004 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved. [References: 31] LG - English PT - Article SB - Current Contents(R)/Clinical Medicine Current Contents(R)/Life Sciences CC - Gastroenterology and Hepatology in Current Contents(R)/Clinical Medicine. Medical Research, Organs & Systems in Current Contents(R)/Life Sciences. EW - 2004 week 36 IN - Reprint available from: Caraceni P Univ Bologna, Policlin S Orsola, Dipartimento Med Interna Cardioangiol & Epatol Via Massarenti 9 I-40138 Bologna Italy Univ Bologna, Policlin S Orsola, Dipartimento Med Interna Cardioangiol & Epatol I-40138 Bologna Italy Univ Bologna, CRBA I-40138 Bologna Italy Univ Bologna, Dipartimento Biochim I-40138 Bologna Italy Univ Bologna, Dipartimento Sci Chirurg Rianimatorie & Trapianti I-40138 Bologna Italy <18> UI - 842OP-0002 DD - ISI Document Solution: 842OP AU - Drennan CL AU - Doukov TI AU - Ragsdale SW MA - cdrennan@mit.edu, tdoukov@slac.stanford.edu, sragsdal@unlnotes.unl.edu RA - Drennan CL TI - The metalloclusters of carbon monoxide dehydrogenase/acetyl-CoA synthase: a story in pictures SO - Journal of Biological Inorganic Chemistry. 9(5):511-515, 2004 Jul. AS - J. Biol. Inorg. Chem 2004 Jul;9(5):511-515 PU - SPRINGER, 233 SPRING STREET, NEW YORK, NY 10013 USA. URL: http://www.springer-ny.com IS - 0949-8257 MH - Acetyl-coa synthase MH - Carbon monoxide dehydrogenase MH - Iron-sulfur clusters MH - Metalloproteins MH - Nickel. MH - Clostridium-thermoaceticum MH - Carboxydothermus-hydrogenoformans MH - Rhodospirillum-rubrum MH - Crystal-structure MH - Acetyl-coenzyme MH - Active-sites MH - Cluster MH - Copper MH - Reveals MH - Nickel. AB - Eight Ni proteins are known and three of these, CO dehydrogenase (CODH), acetyl-CoA synthase (ACS), and hydrogenase, are Ni-Fe-S proteins. In the last three years, the long-awaited structures of CODH and ACS have been solved. The bioinorganic community was shocked, as the structures of the active sites of CODH and ACS, the C- and A-cluster, respectively, which each had been predicted to consist of a [Fe4S4] cluster bridged to a single Ni, revealed unexpected compositions and arrangements. Crystal structures of ACS revealed major differences in protein conformation and in A-cluster composition; for example, a [Fe4S4] cluster bridged to a binuclear center in which one of the metal binding sites was occupied by Ni, Cu, or Zn. Recent studies have revealed Ni-Ni to be the active state, unveiled the source of the heterogeneity that had plagued studies of CODH/ACS for decades, and produced a metal-replacement strategy to generate highly active and nearly homogeneous enzyme. [References: 22] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Chemistry & Analysis in Current Contents(R)/Life Sciences. EW - 2004 week 36 IN - Reprint available from: Drennan CL MIT, Dept Chem Cambridge, MA 02139 USA MIT, Dept Chem Cambridge, MA 02139 USA Stanford Linear Accelerator Ctr Menlo Pk, CA 94025 USA Univ Nebraska, Dept Biochem, Beadle Ctr Lincoln, NE 68588 USA <19> UI - 842OP-0006 DD - ISI Document Solution: 842OP AU - Riordan CG MA - riordan@udel.edu RA - Riordan CG TI - Synthetic chemistry and chemical precedents for understanding the structure and function of acetyl coenzyme A synthase SO - Journal of Biological Inorganic Chemistry. 9(5):542-549, 2004 Jul. AS - J. Biol. Inorg. Chem 2004 Jul;9(5):542-549 PU - SPRINGER, 233 SPRING STREET, NEW YORK, NY 10013 USA. URL: http://www.springer-ny.com IS - 0949-8257 MH - Acetyl coenzyme a synthase MH - Nickel MH - Iron-sulfur clusters MH - Organometallic complexes. MH - Carbon-monoxide dehydrogenase MH - Nickel(i) octaethylisobacteriochlorin anion MH - Clostridium-thermoaceticum MH - Coa synthase MH - Active-site MH - Mechanistic implications MH - Rhodospirillum-rubrum MH - Thioester formation MH - Bridged assemblies MH - Crystal-structures. AB - Acetyl coenzyme A synthase (ACS), found in acetogenic and methanogenic organisms, is responsible for the synthesis and breakdown of acetate. The mechanism by which methylcob(III)alamin, CO and coenzyme A are assembled/disassembled at the active-site A-cluster involves a number of biologically unprecedented intermediates. In the past two years, two protein crystal structures have significantly enhanced the understanding of the structure of the active-site A-cluster, responsible for catalysis. The structure reports spawned a number of important questions regarding the metal ion constitution of the active enzyme, the structure(s) of the spectroscopically identified states and the details of the catalytic mechanism. This Commentary addresses these issues in the framework of existing synthetic and chemical precedent studies aimed at developing rational structure-function correlations and presents structural and reactivity targets for future studies. [References: 79] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Chemistry & Analysis in Current Contents(R)/Life Sciences. EW - 2004 week 36 IN - Reprint available from: Riordan CG Univ Delaware, Dept Chem & Biochem Newark, DE 19716 USA Univ Delaware, Dept Chem & Biochem Newark, DE 19716 USA <20> UI - 840HW-0016 DD - ISI Document Solution: 840HW AU - Dassa B AU - Haviv H AU - Amitai G AU - Pietrokovski S MA - shmuel.pietrokovski@weizmann.ac.il RA - Pietrokovski S TI - Protein splicing and auto-cleavage of bacterial intein-like domains lacking a C '-flanking nucleophilic residue SO - Journal of Biological Chemistry. 279(31):32001-32007, 2004 Jul 30. AS - J. Biol. Chem 2004 Jul 30;279(31):32001-32007 PU - AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC, 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3996 USA. URL: http://www.asbmb.org IS - 0021-9258 MH - Autoprocessing domain MH - Hedgehog MH - Mechanism MH - Evolution MH - Proteasome MH - Glutamine MH - Sequence MH - Terminus MH - Element MH - System. AB - Bacterial intein-like (BIL) domains are newly identified homologs of intein protein-splicing domains. The two known types of BIL domains together with inteins and hedgehog (Hog) auto-processing domains form the Hog/intein (HINT) superfamily. BIL domains are distinct from inteins and Hogs in sequence, phylogenetic distribution, and host protein type, but little is known about their biochemical activity. Here we experimentally study the auto-processing activity of four BIL domains. An A-type BIL domain from Clostridium thermocellum showed both protein-splicing and auto-cleavage activities. The splicing is notable, because this domain has a native Ala C'-flanking residue rather than a nucleophilic residue, which is absolutely necessary for intein protein splicing. B-type BIL domains from Rhodobacter sphaeroides and Rhodobacter capsulatus cleaved their N' or C' ends. We propose an alternative protein-splicing mechanism for the A-type BIL domains. After an initial N-S acyl shift, creating a thioester bond at the N' end of the domain, the C' end of the domain is cleaved by Asn cyclization. The resulting amino end of the C'-flank attacks the thioester bond next at the N' end of the domain. This aminolysis step splices the two flanks of the domain. The B-type BIL domain cleavage activity is explained in the context of the canonical intein protein-splicing mechanism. Our results suggest that the different HINT domains have related biochemical activities of proteolytic cleavages, ligation and splicing. Yet the predominant reactions diverged in each HINT type according to their specific biological roles. We suggest that the BIL domain cleavage and splicing reactions are mechanisms for post-translationally generating protein variability, particularly in extracellular bacterial proteins. [References: 37] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Biochemistry & Biophysics in Current Contents(R)/Life Sciences. EW - 2004 week 36 IN - Reprint available from: Pietrokovski S Weizmann Inst Sci, Dept Mol Genet IL-76100 Rehovot Israel Weizmann Inst Sci, Dept Mol Genet IL-76100 Rehovot Israel <21> UI - 840HW-0057 DD - ISI Document Solution: 840HW AU - Kao MC AU - Di Bernardo S AU - Perego M AU - Nakamaru-Ogiso E AU - Matsuno-Yagi A AU - Yagi T MA - yagi@scripps.edu, yagi2@scripps.edu RA - Matsuno-Yagi A TI - Functional roles of four conserved charged residues in the membrane domain subunit NuoA of the proton-translocating NADH-quinone oxidoreductase from Escherichia coli SO - Journal of Biological Chemistry. 279(31):32360-32366, 2004 Jul 30. AS - J. Biol. Chem 2004 Jul 30;279(31):32360-32366 PU - AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC, 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3996 USA. URL: http://www.asbmb.org IS - 0021-9258 MH - Hereditary optic neuropathy MH - Ubiquinone reductase-activity MH - Aerobic respiratory-chain MH - Mitochondrial complex-i MH - Paracoccus-denitrificans MH - Rhodobacter-capsulatus MH - Peripheral subunits MH - Catalytic-activity MH - Missense mutation MH - Protein-structure. AB - The H+(Na+)-translocating NADH-quinone (Q) oxidoreductase (NDH-1) of Escherichia coli is composed of 13 different subunits (NuoA-N). Subunit NuoA (ND3, Nqo7) is one of the seven membrane domain subunits that are considered to be involved in H+(Na+) translocation. We demonstrated that in the Paracoccus denitrificans NDH-1 subunit, Nqo7 ( ND3) directly interacts with peripheral subunits Nqo6 (PSST) and Nqo4 ( 49 kDa) by using cross-linkers (Di Bernardo, S., and Yagi, T. (2001) FEBS Lett. 508, 385-388 and Kao, M.-C., Matsuno-Yagi, A., and Yagi, T. ( 2004) Biochemistry 43, 3750-3755). To investigate the structural and functional roles of conserved charged amino acid residues, a nuoA knock-out mutant and site-specific mutants K46A, E51A, D79N, D79A, E81Q, E81A, and D79N/E81Q were constructed by utilizing chromosomal DNA manipulation. In terms of immunochemical and NADH dehydrogenase activity-staining analyses, all site-specific mutants are similar to the wild type, suggesting that those NuoA site-specific mutations do not significantly affect the assembly of peripheral subunits in situ. In addition, site-specific mutants showed similar deamino-NADH-K3Fe(CN)(6) reductase activity to the wild type. The K46A mutation scarcely inhibited deamino-NADH-Q reductase activity. In contrast, E51A, D79A, D79N, E81A, and E81Q mutation partially suppressed deamino-NADH-Q reductase activity to 30, 90, 40, 40, and 50%, respectively. The double mutant D79N/E81Q almost completely lost the energy-transducing NDH-1 activities but did not display any loss of deamino-NADH-K3Fe(CN)(6) reductase activity. The possible functional roles of residues Asp-79 and Glu-81 were discussed. [References: 55] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Biochemistry & Biophysics in Current Contents(R)/Life Sciences. EW - 2004 week 36 IN - Reprint available from: Matsuno-Yagi A Scripps Res Inst, Dept Mol & Expt Med, Div Biochem 10666 N Torrey Pines Rd La Jolla, CA 92037 USA Scripps Res Inst, Dept Mol & Expt Med, Div Biochem La Jolla, CA 92037 USA Scripps Res Inst, Dept Mol & Expt Med, Div Cellular Biol La Jolla, CA 92037 USA <22> UI - 840HW-0060 DD - ISI Document Solution: 840HW AU - Alric J AU - Yoshida M AU - Nagashima KVP AU - Hienerwadel R AU - Parot P AU - Vermeglio A AU - Chen SWW AU - Pellequer JL MA - jlpellequer@cea.fr RA - Pellequer JL TI - Two distinct binding sites for high potential iron-sulfur protein and cytochrome C on the reaction center-bound cytochrome of Rubrivivax gelatinosus SO - Journal of Biological Chemistry. 279(31):32545-32553, 2004 Jul 30. AS - J. Biol. Chem 2004 Jul 30;279(31):32545-32553 PU - AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC, 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3996 USA. URL: http://www.asbmb.org IS - 0021-9258 MH - Photosynthetic reaction-center MH - Bacterium rhodovulum-sulfidophilum MH - Reaction-center complex MH - Electron-transfer MH - Rhodopseudomonas-viridis MH - Purple bacterium MH - Rhodoferax-fermentans MH - Directed mutagenesis MH - Crystal-structure MH - Subunit. AB - The photosynthetic cyclic electron transfer of the purple bacterium Rubrivivax gelatinosus, involving the cytochrome bc(1) complex and the reaction center, can be carried out via two pathways. A high potential iron-sulfur protein (HiPIP) acts as the in vivo periplasmic electron donor to the reaction center (RC)-bound cytochrome when cells are grown under anaerobic conditions in the light, while cytochrome c(8) is the soluble electron carrier for cells grown under aerobic conditions in the dark. A spontaneous reversion of R. gelatinosus C244, a defective mutant in synthesis of the RC-bound cytochrome by insertion of a Km(r) cassette leading to gene disruption with a slow growth rate, restores the normal photosynthetic growth. This revertant, designated C244-P1, lost the Kmr cassette but synthesized a RC-bound cytochrome with an external 77-amino acid insertion derived from the cassette. We characterized the RC-bound cytochrome of this mutant by EPR, time-resolved optical spectroscopy, and structural analysis. We also investigated the in vivo electron transfer rates between the two soluble electron donors and this RC-bound cytochrome. Our results demonstrated that the C244-P1 RC-bound cytochrome is still able to receive electrons from HiPIP, but it is no longer reducible by cytochrome c(8). Combining these experimental and theoretical protein-protein docking results, we conclude that cytochrome c(8) and HiPIP bind the RC-bound cytochrome at two distinct but partially overlapping sites. [References: 46] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Biochemistry & Biophysics in Current Contents(R)/Life Sciences. EW - 2004 week 36 IN - Reprint available from: Pellequer JL CEA Valrho, Ctr Marcoule, DSV, DIEP,SBTN BP 17171 F-30207 Bagnols Sur Ceze France CEA Valrho, Ctr Marcoule, DSV, DIEP,SBTN F-30207 Bagnols Sur Ceze France CEA Aix Marseille 2, Lab Genet & Biophys Plantes, CNRS, UMR 6191 F-13288 Marseille France UMR 6191 CNRS CEA Aix Marseille 2, CEA Cadarache, Direct Sci Vivant, Dept Ecophysiol Vegetale & Microbiol,Lab Bioenerg F-13108 St Paul Les Durance France Tokyo Metropolitan Univ, Dept Biol Tokyo 1920397 Japan <23> UI - 842YD-0056 DD - ISI Document Solution: 842YD AU - Ono S AU - Sone N AU - Yoshida M AU - Suzuki T MA - myoshida@res.titech.ac.jp RA - Yoshida M TI - ATP synthase that lacks F-0 alpha-subunit - Isolation, properties, and indication of F(0)b(2)-subunits as an anchor rail of a rotating c-ring SO - Journal of Biological Chemistry. 279(32):33409-33412, 2004 Aug 6. AS - J. Biol. Chem 2004 Aug 6;279(32):33409-33412 PU - AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC, 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3996 USA. URL: http://www.asbmb.org IS - 0021-9258 MH - Coupling proton movements MH - Escherichia-coli MH - Cross-linking MH - Thermophilic bacterium MH - Epsilon-subunit MH - Rotary motor MH - F-0 complex MH - Adenosine-triphosphatase MH - Molecular architecture MH - F1f0-atp synthase. AB - In a rotary motor F1F0-ATP synthase, F-0 works as a proton motor; the oligomer ring of F(0)c-subunits (c-ring) rotates relative to the F(0)ab(2) domain as protons pass through F-0 down the gradient. F(0)ab(2) must exert dual functions during rotation, that is, sliding the c-ring ( motor drive) while keeping the association with the c-ring ( anchor rail). Here we have isolated thermophilic F1F0(- a) which lacks F(0)a. F1F0(-a) has no proton transport activity, and F-0(-a) does not work as a proton channel. Interestingly, ATPase activity of F1F0(-a) is greatly suppressed, even though its F-1 sector is intact. Most likely, F(0)b(2) associates with the c-ring as an anchor rail in the intact F1F0; without F(0)a, this association prevents rotation of the c-ring ( and hence the gamma-subunit), which disables ATP hydrolysis at F-1. Functional F1F0 is easily reconstituted from purified F(0)a and F1F0(-a), and thus F(0)a can bind to its proper location on F1F0( - a) without a large rearrangement of other-subunits. [References: 38] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Biochemistry & Biophysics in Current Contents(R)/Life Sciences. EW - 2004 week 36 IN - Reprint available from: Yoshida M Tokyo Inst Technol, Chem Resources Lab Nagatsuta 4259 Yokohama Kanagawa 2268503 Japan Tokyo Inst Technol, Chem Resources Lab Yokohama Kanagawa 2268503 Japan Japan Sci & Technol Corp, ERATO, ATP Syst Project Yokohama Kanagawa 2260026 Japan <24> UI - 841DC-0005 DD - ISI Document Solution: 841DC AU - Huang H AU - Li F AU - Alvarez RA AU - Ash JD AU - Anderson RE MA - robert-anderson@ouhsc.edu RA - Anderson RE TI - Downregulation of ATP synthase subunit-6, cytochrome c oxidase-III, and NADH dehydrogenase-3 by bright cyclic light in the rat retina SO - Investigative Ophthalmology & Visual Science. 45(8):2489-2496, 2004 Aug. AS - Invest. Ophthalmol. Vis. Sci 2004 Aug;45(8):2489-2496 PU - ASSOC RESEARCH VISION OPHTHALMOLOGY INC, 12300 TWINBROOK PARKWAY, ROCKVILLE, MD 20852-1606 USA IS - 0146-0404 MH - Induced photoreceptor degeneration MH - Fibroblast-growth-factor MH - Differential display MH - Oxygen distribution MH - Induced apoptosis MH - Thyroid-hormone MH - Gene-expression MH - Constant-light MH - Protein-levels MH - Cells. AB - PURPOSE. Retinas of albino rats born and raised in bright cyclic light (300-800 lux) are less susceptible to light-induced apoptosis than retinas of animals born and raised in dim cyclic light (5 lux). In this study, the objective was to study the mechanisms of neuroprotection in the bright cyclic light-reared retina by identification of differentially expressed genes with differential display (DD)-PCR. METHODS. Albino rats were born and raised in 5- or 400-lux cyclic light (12 hours on/off). At 6 to 8 weeks of age, animals were either killed to harvest retinas or exposed to 1700 lux illumination for 12 or 24 hours. The neuroprotection of 400-lux cyclic light rearing was evaluated by DNA fragmentation and quantitative histology. The differentially expressed candidate genes were identified by DD-PCR. Northern blot analysis was used to quantitate differential expression of selected genes. Differential expression of protein was determined by Western blot and enzyme activity analysis. Cellular localization of transcripts was determined by in situ hybridization. RESULTS. DNA fragmentation and quantitative histology results indicated that 400-lux cyclic light rearing protected the retina from light-induced apoptosis compared with 5-lux cyclic light rearing. DD-PCR analysis showed that a 283-bp expressed sequence tag (EST) was downregulated in retinas of rats raised from birth in 400-lux cyclic light. A BLAST search identified the EST as the 3'-terminal sequence of mitochondria-encoded NADH dehydrogenase subunit 3 (ND-3). Northern blot analysis showed that the EST hybridized to two mRNA transcripts, the larger of which was confirmed to encompass the adenosine triphosphate (ATP) synthase subunit 6 (ATPase-6), cytochrome c oxidase subunit III (CO-III), ND-3, and tRNA-Gly. Northern blot analysis demonstrated that CO-III and ATPase-6 were downregulated 1.8- and 2.3-fold by 400-lux cyclic light compared with 5-lux cyclic light, respectively; however, there was no change in cytochrome c oxidase subunit I and II (CO-I and -II) or in 12S ribosomal RNA (12S rRNA), a mitochondrial housekeeping gene. Western blot analysis using anti-CO-III antibody showed more CO-III protein in retinal mitochondria from dim-light-raised rats. The enzyme activity of CO was two times higher in retinal homogenates from dim-light-raised rats than those from bright-light-raised rats. In situ hybridization using a S-35-labeled CO-III probe showed that the CO-III transcript was present and downregulated in most of the retinal layers of bright-light-reared animals. CONCLUSIONS. Rearing in cyclic light at 400-lux downregulates the expression of ATPase-6, CO-III, and ND-3 compared with rearing in 5-lux cyclic light. The authors hypothesize that these changes are adaptive responses to light stress that provide neuroprotection to retinal cells by elevating the level of stress-related factors and reducing the level of oxidized cytochrome c, the form that activates the apoptotic cascade of cell death. [References: 43] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Medical Research, Organs & Systems in Current Contents(R)/Life Sciences. EW - 2004 week 36 IN - Reprint available from: Anderson RE Univ Oklahoma, Hlth Sci Ctr, Dean A McGee Eye Inst, Dept Ophthalmol 608 Stanton L Young Blvd Oklahoma City, OK 73104 USA Univ Oklahoma, Hlth Sci Ctr, Dean A McGee Eye Inst, Dept Ophthalmol Oklahoma City, OK 73104 USA Univ Oklahoma, Hlth Sci Ctr, Dept Cell Biol Oklahoma City, OK 73104 USA Univ Oklahoma, Hlth Sci Ctr, Dept Biochem & Mol Biol Oklahoma City, OK 73104 USA <25> UI - 841EV-0004 DD - ISI Document Solution: 841EV AU - Subhash N AU - Mohanan CN AU - Mallia RJ AU - Muralidharan V MA - subhashn@vsnl.com RA - Subhash N TI - Quantification of stress adaptation by laser-induced fluorescence spectroscopy of plants exposed to engine exhaust emission and drought SO - Functional Plant Biology. 31(7):709-719, 2004. AS - Funct. Plant Biol 2004;31(7):709-719 PU - C S I R O PUBLISHING, 150 OXFORD ST, PO BOX 1139, COLLINGWOOD, VICTORIA 3066, AUSTRALIA. URL: http://www.publish.csiro.au IS - 1445-4408 MH - Air pollution MH - Engine exhaust emissions MH - F685 / f730 ratio MH - Laser-induced chlorophyll fluorescence MH - Open-top chamber MH - Stress adaptation index MH - Vitality index MH - Water stress. MH - Red chlorophyll fluorescence MH - Open-top chambers MH - Abies l karst MH - Sulfur-dioxide MH - Air-pollutants MH - Photosynthetic activity MH - Green plants MH - Ozone MH - Parameters MH - Leaves. AB - The effects of drought and petrol engine exhaust pollutants, such as SO2 and NO2 and suspended particulate matter (SPM), on the photosynthetic activity of colocasia [Colocasia esculenta (L.) Schott], kacholam (Kaempferia galanga L.) and tapioca (Manihot esculenta Crantz) plants were studied from in vivo laser-induced chlorophyll fluorescence (LICF) spectra. An open-top chamber (OTC) of 2.5 m diameter and 3 m height incorporating an air-filtering unit was developed for this study. Plants grown inside the OTC were exposed to exhaust emissions from a two-stroke Birla Yamaha genset for 10 d, while a control group was maintained outside. Gaseous pollutants and SPM present inside the OTC during the exposure period were measured with a high-volume air sampler. The steady-state LICF spectra of the control and treated plants were recorded in the 650-750-nm region. Fluorescence induction kinetics (Kautsky effect) was also recorded during the stress period from dark-adapted intact plant leaves at the chlorophyll bands of 685 and 730 nm. The vitality indexes (Rfd-685 and Rfd-730) and stress adaptation index (Ap) derived from the induction kinetics were utilised along with the chlorophyll fluorescence intensity ratio (F685/F730) for evaluation of stress-induced changes in plants. It has been observed that F685/F730 ratio increased for all plants inside the OTC whereas the Rfd-685, Rfd-730 and Ap values showed a downward trend with increasing pollution stress. As compared to colocasia and tapioca, kacholam plants showed higher resistance to exhaust emission and water stress as well as better capacity to regain its photosynthetic functioning on removal of the stress. Results of this study demonstrate the capability of stress adaptation index for early quanti. cation of the functional impairment of photosynthetic apparatus in different species of plants due to air pollution and drought stresses. [References: 62] 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 - 2004 week 36 IN - Reprint available from: Subhash N Ctr Earth Sci Studies PB 7250,Thuruvikkal PO Trivandrum 695031 Kerala India Ctr Earth Sci Studies Trivandrum 695031 Kerala India <26> UI - 841EV-0006 DD - ISI Document Solution: 841EV AU - Perez-Torres E AU - Garcia A AU - Dinamarca J AU - Alberdi M AU - Gutierrez A AU - Gidekel M AU - Ivanov AG AU - Huner NPA AU - Corcuera LJ AU - Bravo LA MA - lebravo@udec.cl RA - Bravo LA TI - The role of photochemical quenching and antioxidants in photoprotection of Deschampsia antarctica SO - Functional Plant Biology. 31(7):731-741, 2004. AS - Funct. Plant Biol 2004;31(7):731-741 PU - C S I R O PUBLISHING, 150 OXFORD ST, PO BOX 1139, COLLINGWOOD, VICTORIA 3066, AUSTRALIA. URL: http://www.publish.csiro.au IS - 1445-4408 MH - Antarctic angiosperms MH - Ascorbate peroxidase MH - Glutathione reductase MH - Low temperature MH - Non-photochemical quenching MH - Photochemical quenching MH - Photoinhibition MH - Reactive oxygen species MH - Superoxide dimutase MH - Xanthophyll cycle. MH - Xanthophyll cycle MH - Oxidative stress MH - Superoxide dismutases MH - Vascular plants MH - Arabidopsis-thaliana MH - Energy-dissipation MH - Hydrogen-peroxide MH - Light stress MH - Excess light MH - Photoinhibition. AB - Deschampsia antarctica Desv. (Poaceae) is the only grass that grows in the maritime Antarctic. Constant low temperatures and episodes of high light are typical conditions during the growing season at this latitude. These factors enhance the formation of active oxygen species and may cause photoinhibition. Therefore, an efficient mechanism of energy dissipation and/or scavenging of reactive oxygen species (ROS) would contribute to survival in this harsh environment. In this paper, non-acclimated and cold-acclimated D. antarctica were subjected to high light and/or low temperature for 24 h. The contribution of non-photochemical dissipation of excitation light energy and the activities of detoxifying enzymes in the development of resistance to chilling induced photoinhibition were studied by monitoring PSII fluorescence, total soluble antioxidants, and pigments contents and measuring variations in activity of superoxide dismutase (SOD;EC1.15.1.1), ascorbate peroxidase (APX;EC 1.11.1.11), and glutathione reductase (GR; EC 1.6.4.2). The photochemical efficiency of PSII, measured as F-v/F-m, and the yield of PSII electron transport (PhiPSII) both decreased under high light and low temperatures. In contrast, photochemical quenching (qP) in both non-acclimated and cold-acclimated plants remained relatively constant (approximately 0.8) in high-light-treated plants. Unexpectedly, qP was lower (0.55) in cold-acclimated plants exposed to 4degreesC and low light intensity. Activity of SOD in cold-acclimated plants treated with high light at low temperature showed a sharp peak 2-4 h after the beginning of the experiment. In cold-acclimated plants APX remained high with all treatments. Activity of GR decreased in cold-acclimated plants. Compared with other plants, D. antarctica exhibited high levels of SOD and APX activity. Pigment analyses show that the xanthophyll cycle is operative in this plant. We propose that photochemical quenching and particularly the high level of antioxidants help D. antarctica to resist photoinhibitory conditions. The relatively high antioxidant capacity of D. antarctica may be a determinant for its survival in the harsh Antarctic environment. [References: 57] 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 - 2004 week 36 IN - Reprint available from: Bravo LA Concepcion Univ, Fac Ciencias Nat & Oceanog, Dept Bot Casilla 160-C Concepcion Chile Concepcion Univ, Fac Ciencias Nat & Oceanog, Dept Bot Concepcion Chile Univ Austral Chile, Fac Ciencias, Inst Bot Valdivia Chile Univ La Frontera, Fac Ciencias Agropecuarias & Forestales, Lab Fisiol & Biol Mol Vegetal Temuco Chile Univ Western Ontario, Dept Biol London ON N6A 5B7 Canada <27> UI - 841EV-0007 DD - ISI Document Solution: 841EV AU - Krause GH AU - Grube E AU - Koroleva OY AU - Barth C AU - Winter K MA - ghkrause@uni-duesseldorf.de RA - Krause GH TI - Do mature shade leaves of tropical tree seedlings acclimate to high sunlight and UV radiation? SO - Functional Plant Biology. 31(7):743-756, 2004. AS - Funct. Plant Biol 2004;31(7):743-756 PU - C S I R O PUBLISHING, 150 OXFORD ST, PO BOX 1139, COLLINGWOOD, VICTORIA 3066, AUSTRALIA. URL: http://www.publish.csiro.au IS - 1445-4408 MH - Anacardium excelsum MH - Ascorbate MH - Calophyllum longifolium MH - Chlorophyll a/b MH - Ficus insipida MH - Photosynthetic pigments MH - Virola surinamensis.. MH - Xanthophyll-cycle activity MH - High-light stress MH - Thermal-energy dissipation MH - Spinach spinacia-oleracea MH - Photosystem-ii MH - Ultraviolet-radiation MH - Chlorophyll fluorescence MH - Pigment composition MH - Photosynthetic apparatus MH - Higher-plants. AB - Seedlings of neotropical forest trees grown in low light were exposed to 0.5-9 h d(-1) direct sunlight, for up to 3 months, to test the capability of mature shade leaves to acclimate to full solar visible and UV radiation. Photosynthetic pigments and the antioxidant, ascorbate, were analysed in leaves of two pioneer and two late-succession species. Seedlings of one or two of these species were used to assess further acclimative responses. Sun-exposure for 0.5 or 1 h d(-1) resulted in strongly decreased alpha-carotene and increased beta-carotene and lutein levels. The pool size of xanthophyll-cycle pigments (sum of viola-, anthera- and zeaxanthin) was increased and their turnover was enhanced. These changes were associated with an increase in the capacity of non-photochemical fluorescence quenching and its 'energy-dependent' component, qE, and with reduced susceptibility to photoinhibition of PSII. Prolonged exposure to full direct sunlight (approximately 4 or 9 h d(-1)) resulted in a marked decrease of chlorophyll a+b content and increase in chlorophyll a/b ratios and the pool of xanthophyll-cycle pigments (based on chlorophyll), leading to extremely high zeaxanthin levels during high-light periods. Contents of ascorbate and UV-B-absorbing substances were substantially increased. PSI activity exhibited a response to full sunlight that is characteristic of sun leaves. Rates of net photosynthetic CO2 assimilation under saturating light were increased. The data show that mature shade leaves of seedlings of both early- and late-succession tree species can substantially acclimate to full-sunlight conditions by employing similar physiological mechanisms. [References: 55] 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 - 2004 week 36 IN - Reprint available from: Krause GH Smithsonian Trop Res Inst Apartado 2072 Balboa Ancon Panama Smithsonian Trop Res Inst Balboa Ancon Panama Univ Dusseldorf, Inst Plant Biochem D-40225 Dusseldorf Germany <28> UI - 841LJ-0009 DD - ISI Document Solution: 841LJ AU - Brevik A AU - Andersen LF AU - Karlsen A AU - Trygg KU AU - Blomhoff R AU - Drevon CA MA - asgeir.brevik@basalmed.uio.no RA - Brevik A TI - Six carotenoids in plasma used to assess recommended intake of fruits and vegetables in a controlled feeding study SO - European Journal of Clinical Nutrition. 58(8):1166-1173, 2004 Aug. AS - Eur. J. Clin. Nutr 2004 Aug;58(8):1166-1173 PU - NATURE PUBLISHING GROUP, MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND. URL: http://www.nature.com IS - 0954-3007 MH - Carotenoids MH - Biomarker MH - Feeding study MH - Crossover. MH - Beta-carotene MH - Cancer prevention MH - Epidemiologic evidence MH - Alpha-carotene MH - Lung-cancer MH - Biomarkers MH - Intervention MH - Diets MH - Consumption MH - Nutrition. AB - Background: There is a need for objective and universally applicable biomarkers for the intake of foods believed to affect human health. Objective: The purpose of this feeding study was to test whether plasma concentrations of carotenoids could be used to distinguish recommended consumption of mixed fruits and vegetables ( five a day) from the current national intake of fruits and vegetables ( two a day). Design: A strict crossover design was chosen to correct for observed interindividual variations in carotenoid response. A total of 40 healthy subjects were included in the study. After 1 week run-in period with no fruits and vegetables in the diet, one group was given two portions ( 300 g) of fruits and vegetables daily, while another group was given five portions (750 g) for 14 days. Following a 2 week wash-out period and 1 week run-in, the regimens were switched between the groups. Fruits and vegetables were combined to match a typical Norwegian diet. Results: Enhanced intake from two to five portions of mixed fruits and vegetables increased plasma concentrations of alpha-carotene (P = 0.033) and lutein (P = 0.051) in a crossover analysis. Analysis of data in the parallel part of the study revealed differences between the high and low intake for plasma concentrations of alpha-carotene (P = 0.013) and beta-carotene (P = 0.016). A trend was also evident for plasma concentrations of lycopene (P = 0.057) and lutein (P = 0.076) in the parallel analysis. No effect of high vs low intake of fruits and vegetables was observed for plasma concentrations of beta-cryptoxanthin, zeaxanthin, cholesterol and triacylglycerols. Conclusion: The study indicates that plasma concentration of alpha-carotene, beta-carotene and lutein may be used to assess changes of fruit and vegetable intake corresponding to an increase from the present national intake in Norway to the recommended amount of five portions of fruits and vegetables daily. Sponsorship: Norwegian Research Council, National Nutrition Council, Throne Holst Foundation for Nutrition Research and Freia Chokoladefabriks Medisinske Fond. [References: 35] LG - English PT - Article SB - Current Contents(R)/Clinical Medicine Current Contents(R)/Life Sciences CC - Endocrinology, Metabolism & Nutrition in Current Contents(R)/Clinical Medicine. Endocrinology, Nutrition & Metabolism in Current Contents(R)/Life Sciences. EW - 2004 week 36 IN - Reprint available from: Brevik A Univ Oslo, Inst Nutr Res, Sch Med POB 1046 N-0316 Oslo Norway Univ Oslo, Inst Nutr Res, Sch Med N-0316 Oslo Norway <29> UI - 841OU-0002 DD - ISI Document Solution: 841OU AU - Kindzelskii A AU - Petty HR MA - hpetty@umich.edu RA - Petty HR TI - Fluorescence spectroscopic detection of mitochondrial flavoprotein redox oscillations and transient reduction of the NADPH oxidase-associated flavoprotein in leukocytes SO - European Biophysics Journal. 33(4):291-299, 2004 Jul. AS - Eur. Biophys. J. Biophys. Lett 2004 Jul;33(4):291-299 PU - SPRINGER, 233 SPRING STREET, NEW YORK, NY 10013 USA. URL: http://www.springer-ny.com IS - 0175-7571 MH - Flavoprote in MH - Leukocyte MH - Mitochondria MH - Nadph oxidase MH - Fluorescence spectroscopy. MH - Rat-liver mitochondria MH - Muscle-fibers MH - Neutrophils MH - Metabolism MH - Cells MH - Autofluorescence MH - Frequency MH - Patterns MH - Release. AB - Steady-state and time-resolved fluorescence spectroscopy and fluorescence microscopy of leukocyte flavoproteins have been performed. Both living human peripheral blood monocytes and neutrophils have been utilized as experimental models, as the former relies much more heavily on mitochondrial metabolism for energy production than the latter. We confirm previous studies indicating that cellular flavoproteins absorb at 460 nm and emit at 530 nm, very similar to that of the FAD moiety. Furthermore, the emission properties of intracellular flavoproteins were altered by the metabolic inhibitors rotenone, antimycin A, azide, cyanide, DNP (2,4-dinitrophenol), and FCCP [carbonyl cyanide p-(trifluoromethoxy)phenylhydrazone]. Kinetic studies revealed flavoprotein emission oscillations in both monocytes and neutrophils. The flavoprotein intensity oscillations correlated with the physiological status of the cell and the nature of membrane receptor ligation. Microscopy revealed the presence of flavoprotein fluorescence in association with the plasma membrane, intracellular granules and distributed throughout the cytoplasm, presumably within mitochondria. Metabolic inhibitors such as cyanide suggest that the plasma membrane and granular components are cyanide-insensitive and therefore are likely associated with the flavoprotein component of the NADPH oxidase, which is located in these two compartments. This interpretation was found to be consistent with structural localization of the NADPH oxidase using an antibody molecule specific for this protein. Using peripheral blood neutrophils, which display less active mitochondria, and time-resolved emission spectroscopy, we show that the NADPH oxidase-associated flavoprotein undergoes a periodic transient reduction of about 54 +/- 2 ms in living cells. This finding is consistent with prior studies indicating that propagating substrate (NADPH) waves periodically promote electron transport across the NADPH oxidase. [References: 26] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Biochemistry & Biophysics in Current Contents(R)/Life Sciences. EW - 2004 week 36 IN - Reprint available from: Petty HR Univ Michigan, Sch Med, Dept Ophthalmol & Visual Sci 1000 Wall St Ann Arbor, MI 48105 USA Univ Michigan, Sch Med, Dept Ophthalmol & Visual Sci Ann Arbor, MI 48105 USA Univ Michigan, Sch Med, Dept Microbiol & Immunol Ann Arbor, MI 48105 USA <30> UI - 842WO-0025 DD - ISI Document Solution: 842WO AU - Endo R AU - Omasa K MA - aomasa@mail.ecc.u-tokyo.ac.jp RA - Omasa K TI - Chlorophyll fluorescence imaging of individual algal cells: Effects of herbicide on Spirogyra distenta at different growth stages SO - Environmental Science & Technology. 38(15):4165-4168, 2004 Aug 1. AS - Environ. Sci. Technol 2004 Aug 1;38(15):4165-4168 PU - AMER CHEMICAL SOC, 1155 16TH ST, NW, WASHINGTON, DC 20036 USA. URL: http://pubs.acs.org IS - 0013-936X MH - Confocal microscopy MH - Photosystem-ii MH - Intact leaves MH - Plant stress MH - Yield MH - Photosynthesis MH - Phytoplankton MH - Pollution MH - Toxicity MH - System. AB - Serious environmental degradation of aquatic ecosystems has been caused by eutrophication and by pollutants such as herbicides. Therefore, measurement of in situ algal photosynthetic activity is important for environmental monitoring. With ordinary nonimaging fluorometers, algal chlorophyll fluorescence can be measured easily, but heterogeneity within samples cannot be detected. Effects of a herbicide preparation containing 3-(3,4-dichlorophenyl)1,1-dimethylurea (DCMU) on photosynthetic activity at different growth stages of Spirogyra distenta were investigated by using a computer-aided microscopic imaging system for chlorophyll a fluorescence. Photosystem II photochemical yield (phi(PSII)) images were used to diagnose photosynthetic activity of spiral filate chloroplasts in algal cells. The herbicide treatment caused a stronger decline in phi(PSII) values in younger than in mature algae cells. This result indicated that heterogeneity within algal samples should be considered when algae are used for environmental monitoring. Thus, measurement of chlorophyll fluorescence from young and mature chloroplasts with a microscopic imaging system makes it possible to improve the sensitivity for monitoring the environmental degradation of aquatic ecosystems. [References: 28] LG - English PT - Article SB - Current Contents(R)/Agriculture, Biology & Environmental Sciences Current Contents(R)/Engineering, Computing & Technology CC - Environment/Ecology in Current Contents(R)/Agricultural, Biology & Environmental Sciences. Environmental Engineering & Energy in Current Contents(R)/Engineering, Computing & Technology. EW - 2004 week 36 IN - Reprint available from: Omasa K Univ Tokyo, Grad Sch Agr & Life Sci 1-1-1 Yayoi Bunkyo Tokyo 1138657 Japan Univ Tokyo, Grad Sch Agr & Life Sci Tokyo 1138657 Japan <31> UI - 841XG-0018 DD - ISI Document Solution: 841XG AU - Caffarri S AU - Croce R AU - Cattivelli L AU - Bassi R MA - bassi@sci.univr.it RA - Bassi R TI - A look within LHCII: Differential analysis of the Lhcbl-3 complexes building the major trimeric antenna complex of higher-plant photosynthesis SO - Biochemistry. 43(29):9467-9476, 2004 Jul 27. AS - Biochemistry 2004 Jul 27;43(29):9467-9476 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 - A/b-binding-protein MH - Photosystem-ii membranes MH - Pigment-binding MH - Chlorophyll-a MH - Chromophore-binding MH - In-vitro MH - Maize MH - Organization MH - Fluorescence. AB - The major antenna complex of higher-plant photosynthesis, LHCII, is composed by the products of three genes, namely, Lhcbl-2-3. In this paper, the biochemical and spectroscopic proper-ties of each of the three gene products were investigated. The three complexes were obtained by overexpression of the apoproteins in bacteria and refolding in vitro with purified pigments, thus allowing detection of differences in the structure/function of the pigment-binding gene products. The analyses showed that Lhcb1 and Lhcb2 complexes have similar pigment binding properties, although not identical, while Lhcb3 is clearly different with respect to both pigment binding and spectral properties and cannot produce homotrimers in vitro. Heterotrimers containing Lhcb3 together with Lhcb1 and/or -2 proteins were obtained upon assembly with Lhcb proteins purified from thylakoids. The major functional characteristics of Lhcb3 with respect to Lhcb1 and -2 consisted in (i) a red-shift of one specific chlorophyll a chromophore, strongly affecting the red-most region of the absorption spectrum and (ii) a different specificity for xanthophylls binding to sites L2 and N1. These properties make Lhcb3 a relative sink for excitation energy in isolated heterotrimers with Lhcb1 + Lhcb2, and potentially, a preferential site of regulation of the antenna function in excess light conditions. [References: 55] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Biochemistry & Biophysics in Current Contents(R)/Life Sciences. EW - 2004 week 36 IN - Reprint available from: Bassi R Univ Verona, Dipartimento Sci & Tecnol Str Grazie 15 I-37134 Verona Italy Univ Verona, Dipartimento Sci & Tecnol I-37134 Verona Italy CNR, ITC Ist Biofis, Sez Trento Povo Tn Italy Univ Aix Marseille 2, LGBP, Fac Sci Luminy, Dept Biol F-13288 Marseille 09 France Ist Sperimentale Cerealicoltura I-29017 Fiorenzuola Darda PC Italy <32> UI - 841XG-0019 DD - ISI Document Solution: 841XG AU - Iwaki M AU - Osyczka A AU - Moser CC AU - Dutton PL AU - Rich PR MA - prr@ucl.ac.uk RA - Rich PR TI - ATR-FTIR spectroscopy studies of iron-sulfur protein and cytochrome c(1) in the Rhodobacter capsulatus cytochrome bc(1) complex SO - Biochemistry. 43(29):9477-9486, 2004 Jul 27. AS - Biochemistry 2004 Jul 27;43(29):9477-9486 PU - AMER CHEMICAL SOC, 1155 16TH ST, NW, WASHINGTON, DC 20036 USA. URL: http://pubs.acs.org IS - 0006-2960 MH - Transform infrared-spectroscopy MH - Linked conformational-changes MH - C-oxidase MH - Difference spectroscopy MH - Paracoccus-denitrificans MH - Electron-transfer MH - Escherichia-coli MH - Rhodopseudomonas-sphaeroides MH - Ubiquinol oxidation MH - Crystal-structure. AB - Redox transitions in the Rhodobacter capsulatus cytochrome bc(1) complex were investigated by perfusion-induced attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy combined with synchronous visible spectroscopy, in both the wild type and a cytochrome c(1) point mutant, M183K, in which the midpoint potential of heme was lowered from the wild-type value of 320 mV to 60 mV. Overall redox difference spectra of the wild type and M183K mutant were essentially identical, indicating that the mutation did not cause any major structural perturbation. Spectra were compared with data on the bovine bc(1) complex, and tentative assignments of several bands could be made by comparison with available data on model compounds and crystallographic structures. The bacterial spectra showed contributions from ubiquinone that were much larger than in the bovine enzyme, arising from additional bound and adventitious ubiquinone. The M183K mutant enabled selective reduction of the iron-sulfur protein which in turn allowed the IR redox difference spectra of ISP and cytochrome c, to be deconvoluted at high signal/noise ratios, and features of these spectra are interpreted in light of structural and mechanistic information. [References: 61] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Biochemistry & Biophysics in Current Contents(R)/Life Sciences. EW - 2004 week 36 IN - Reprint available from: Rich PR Univ Coll London, Dept Biol, Glynn Lab Bioenerget Gower St London WC1E 6BT England Univ Coll London, Dept Biol, Glynn Lab Bioenerget London WC1E 6BT England Univ Penn, Johnson Res Fdn, Dept Biochem & Biophys Philadelphia, PA 19104 USA <33> UI - 842BL-0003 DD - ISI Document Solution: 842BL AU - Moret I AU - Gambaro A AU - Piazza R AU - Corami F AU - Ravazzi C AU - Andreoli C AU - Truzzi C AU - Lambertucci L AU - Scarponi G MA - scarponi@univpm.it RA - Scarponi G TI - Chemometric studies in the lagoon of Venice, Italy. Annual evolution of sulphur species and relationship to biogeochemical cycles in lagoon water SO - Annali di Chimica. 94(5-6):373-387, 2004 May-Jun. AS - Ann. Chim 2004 May-Jun;94(5-6):373-387 PU - SOC CHIMICA ITALIANA, VIALE LIEGI 48, I-00198 ROME, ITALY IS - 0003-4592 MH - Equatorial pacific-ocean MH - Dimethyl sulfide MH - North-atlantic MH - Seasonal-variations MH - Atmospheric sulfur MH - Emiliania-huxleyi MH - Surface-water MH - Marine-algae MH - Dmsp MH - Dimethylsulphoniopropionate. AB - During the period March 1997 - March 1998 dimethyl sulphide (DMS), dimethylsulphoniopropionate (DMSP) and carbon disulphide (CS2) were determined weekly in the water of the Lagoon of Venice, Italy (at three stations located in the Giudecca Canal, the San Secondo Canal and the Rio di San Nicolo). At the same time, the following hydrological and biological variables were also measured: tide height, temperature, transmittance, fluorescence, pH, salinity, chlorinity, sulphate, ammonia, nitrite, nitrate, phosphate, silicate, chlorophyll a, phaeopigments, phytoplankton (abundance and biomass). Principal component analysis (PCA), applied as a dimension reduction tool, made it possible to summarize multivariate information in a small number of components, which highlighted the relationships between the temporal evolutions of the sulphur compounds with hydrological and biological variables in the seasonal biogeochemical cycle of the lagoon. In particular the overall temporal cycle, which begins with the development of biological activity in late winter and spring, followed by the predominance of degradation processes during the late summer and the remineralization of nutrients in autumn, is clearly described in the plane of the first two principal components, together with the interrelationships between all the relevant variables. [References: 58] LG - English PT - Article SB - Current Contents(R)/Physical, Chemical & Earth Sciences CC - Chemistry in Current Contents(R)/Physical, Chemical & Earth Sciences. EW - 2004 week 36 IN - Reprint available from: Scarponi G Univ Politecn Marche Ancona, Dipartimento Sci Mare Via Brecce Bianche I-60131 Ancona Italy Univ Politecn Marche Ancona, Dipartimento Sci Mare I-60131 Ancona Italy Univ Ca Foscari, Dipartimento Sci Ambientali I-30123 Venice Italy CNR, Ist Dinam Proc Ambientali I-30123 Venice Italy Univ Padua, Dipartimento Biol I-35121 Padua Italy <34> UI - 841ON-0016 DD - ISI Document Solution: 841ON AU - Kayser EB AU - Morgan PG AU - Sedensky MM MA - philip.morgan@uhhs.com RA - Morgan PG TI - Mitochondrial complex I function affects halothane sensitivity in Caenorhabditis elegans SO - Anesthesiology. 101(2):365-372, 2004 Aug. AS - Anesthesiology 2004 Aug;101(2):365-372 PU - LIPPINCOTT WILLIAMS & WILKINS, 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA. URL: http://www.lww.com/ IS - 0003-3022 MH - Nadh-ubiquinone oxidoreductase MH - Volatile-anesthetics MH - 49-kda subunit MH - Oxidative stress MH - Isoflurane MH - Nematode MH - Mutation MH - Ethanol MH - Protein MH - Gas-1. AB - Background: The gene gas-1 encodes a subunit of complex 1 of the mitochondrial electron transport chain in Caenorhabditis elegans. A mutation in gas-1 profoundly increases sensitivity of C elegans to volatile anesthetics. It is unclear which aspects of mitochondrial function account for the hypersensitivity of the mutant. Methods: Oxidative phosphorylation was determined by measuring mitochondrial oxygen consumption using electron donors specific for either complex I or complex II. Adenosine triphosphate concentrations were determined by measuring luciferase activity. Oxidative damage to mitochondrial proteins was identified using specific antibodies. Results: Halothane inhibited oxidative phosphorylation in isolated wild-type mitochondria within a concentration range that immobilizes intact worms. At equal halothane concentrations, complex I activity but not complex II activity was lower in mitochondria from mutant (gas-1) animals than from wild-type (N2) animals. The halothane concentrations needed to immobilize 50% of N2 or gas-1 animals, respectively, did not reduce oxidative phosphorylation to identical rates in the two strains. In air, adenosine triphosphate concentrations were similar for N2 and gas-1 but were decreased in the presence of halothane only in gas-1 animals. Oxygen tension changed the sensitivity of both strains to halothane. When nematodes were raised in room air, oxidative damage to nutochondrial proteins was increased in the mutant animal compared with the wild type. Conclusions: Rates of oxidative phosphorylation and changes in adenosine triphosphate concentrations by themselves do not control anesthetic-induced immobility of wild-type C. elegans. However. they may contribute to the increased sensitivity to volatile anesthetics of the gas-1 mutant. Oxidative damage to proteins may be an important contributor to sensitivity to volatile anesthetics in C. elegans. [References: 37] LG - English PT - Article SB - Current Contents(R)/Clinical Medicine Current Contents(R)/Life Sciences CC - Anesthesia & Intensive Care in Current Contents(R)/Clinical Medicine. Medical Research, Diagnosis & Treatment in Current Contents(R)/Life Sciences. EW - 2004 week 36 IN - Reprint available from: Morgan PG Univ Hosp Cleveland, Dept Anesthesiol 11100 Euclid Ave Cleveland, OH 44106 USA Univ Hosp Cleveland, Dept Anesthesiol Cleveland, OH 44106 USA Case Western Reserve Univ, Dept Anesthesiol Cleveland, OH 44106 USA <35> UI - 842LI-0009 DD - ISI Document Solution: 842LI AU - Jose J AU - von Schwichow S MA - joachim.jose@uni-diuesseldorf.de RA - Jose J TI - "Cystope tagging" for labeling and detection of recombinant protein expression SO - Analytical Biochemistry. 331(2):267-274, 2004 Aug 15. AS - Anal. Biochem 2004 Aug 15;331(2):267-274 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 - Autodisplay MH - Protein expression MH - Labeling MH - Sorbit dehydrogenase MH - Maleimide MH - Sulfhydryl groups. MH - Aida-i autotransporter MH - Escherichia-coli MH - Surface display MH - Rhodobacter-sphaeroides MH - Sorbitol dehydrogenase MH - Functional display MH - Purification MH - Autodisplay MH - Component MH - Transport. AB - A labeling and detection method, based on the addition of a single cysteine residue at the C terminus of a recombinant protein and the subsequent sulfliydryl-specific Michael addition to the double bond of maleimide and its derivatives, was developed. The method was named "cystope tagging." Sorbit dehydrogenase (SDH) from Rhodobacter sphaeroides, a member of the short-chain dehydrogenase family of proteins that contains three inherent cysteines, was used as a model recombinant protein. By labeling with fluorescein-maleimide, it was demonstrated that only the single accessory cysteine is accessible under nonreducing conditions. After the addition of P-mercaptoethanol, the inherent cysteines of SDH were also detectable by coupling to fluorescein-maleimide. The data were obtained using Autodisplay, an efficient surface expression system in Escherichia coli, but the method presented in this article represents a rather general solution for analyzing the expression of recombinant proteins, irrespective of the expression system used. The authors conclude that cystope tagging is an interesting alternative to other tagging methods applied in recombinant protein techniques. (C) 2004 Elsevier Inc. All rights reserved. [References: 19] LG - English PT - Article SB - Current Contents(R)/Life Sciences CC - Biochemistry & Biophysics in Current Contents(R)/Life Sciences. EW - 2004 week 36 IN - Reprint available from: Jose J Univ Dusseldorf, Inst Pharmaceut Chem, Dept Bioanalyt Univ Str 1 D-40225 Dusseldorf Germany Univ Saarland D-66041 Saarbrucken Germany <36> UI - 841ET-0036 DD - ISI Document Solution: 841ET AU - Schaumberg DA AU - Liu SM AU - Seddon JM AU - Willett WC AU - Hankinson SE MA - dschaumberg@rics.bwh.harvard.edu RA - Schaumberg DA TI - Dietary glycemic load and risk of age-related cataract SO - American Journal of Clinical Nutrition. 80(2):489-495, 2004 Aug. AS - Am. J. Clin. Nutr 2004 Aug;80(2):489-495 PU - AMER SOC CLINICAL NUTRITION, 9650 ROCKVILLE PIKE, SUBSCRIPTIONS, RM L-3300, BETHESDA, MD 20814-3998 USA. URL: http://www.faseb.org/ascn IS - 0002-9165 MH - Epidemiology MH - Cataract MH - Cataract surgery MH - Risk factors MH - Glycemic load MH - Glycemic index MH - Diet MH - Carbohydrates. MH - Coronary-heart-disease MH - C-reactive protein MH - Diabetes-mellitus MH - Oxidative stress MH - Polyol pathway MH - Index foods MH - Us women MH - Lens MH - Questionnaire MH - Opacities. AB - Background: Metabolism of many of the most commonly consumed carbohydrates in the United States results in a high plasma glucose response, which can be quantified by the glycemic load. Although hyperglycemia is a risk factor for cataract, there is no information on the potential effect of a high dietary glycemic load on the incidence of age-related cataract. Objective: Our objective was to prospectively examine the association between dietary glycemic load and incident age-related cataract. Design: We studied 2 cohorts-71 919 women and 39 926 men-aged greater than or equal to45 y who had no previous diagnosis of cataract, diabetes mellitus, or cancer and who were followed for 14 and 12 y, respectively, for the occurrence of cataract extraction. We calculated dietary glycemic load from data reported on multiple validated food-frequency questionnaires and used pooled logistic regression models to estimate the association with incident cataract extraction. We performed analyses separately for each cohort and then calculated pooled estimates across cohorts. Results: During 980 683 person-years of follow-up, we confirmed 4865 incident age-related cataract extractions. After adjustment for age, cigarette smoking, body mass index, total caloric intake, dietary intake of lutein and zeaxanthin, and alcohol consumption, there was no significant relation of dietary glycemic load to risk of cataract extraction (P for trend = 0.10). The pooled relative risk between the highest and lowest quintiles of dietary glycemic load was 0.95 (95% CI: 0.81. 1.11: P for heterogeneity by cohort = 0.1). Conclusion: These prospective epidemiologic data do not support the hypothesis that a high dietary glycemic load, primarily a result of consumption of refined carbohydrates, increases the risk of cataract extraction. [References: 36] LG - English PT - Article SB - Current Contents(R)/Clinical Medicine Current Contents(R)/Life Sciences CC - Endocrinology, Metabolism & Nutrition in Current Contents(R)/Clinical Medicine. Endocrinology, Nutrition & Metabolism in Current Contents(R)/Life Sciences. EW - 2004 week 36 IN - Reprint available from: Schaumberg DA Brigham & Womens Hosp, Channing Lab, Div Prevent Med 900 Commonwealth Ave E Boston, MA 02115 USA Brigham & Womens Hosp, Channing Lab, Div Prevent Med Boston, MA 02115 USA Harvard Univ, Sch Med, Dept Ophthalmol Boston, MA 02115 USA Harvard Univ, Sch Publ Hlth, Dept Epidemiol Boston, MA 02115 USA Harvard Univ, Sch Publ Hlth, Dept Nutr Boston, MA 02115 USA