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PHOTOBIOCHEMISTRY AND PHOTOBIOPHYSICS 1982年第5-6期4卷 265-273页

作者： BAKER, NR STRASSER, RJ UNIV ESSEX DEPT BIOL COLCHESTER CO4 3SQ ESSEX ENGLAND UNIV STUTTGART INST BIOL DEPT BIOENERGET D-7000 STUTTGART 80 FED REP GER

The development of excitation energy transfer between photosystem [PS] II and PS I was examined by analyses of the 695 and 735 nm fluorescence emission kinetics of greening etiolated bean leaves frozen to ***. K. The action spectra for this intersystem excitation energy transfer during greening were determined from the excitation spectra of the variable fluorescence at 735 nm. Excitation energy transfer between 2 photosystems developed after the appearance of primary photochemical activity of the reaction centers of both photosystems and increased during greening. Initially longer wavelength absorbing chlorophyll forms associated with PS II predominantly contributed to the energy transfer, with chlorophyll species absorbing at shorter wavelengths only becoming significantly involved at later stages of development.

关键词： PS I, PS II photosystems I and II respectively f 1 , f 2 chlorophyll fluorescence emission from PS I and PS II, respectively Subscripts (m) (0) and (v) designate the maximum, minimal and variable levels of fluorescence, respectively k 21 rate constant for total energy transfer from PS II to PS I LHCP light-harvesting chlorophyll a / b -protein complex P 1 , P 2 exciton densities within PS I and PS II, respectively p 2b probability of an exciton in PS II chlorophylls being deexcited during transfer to a PS II reaction centre p b2 probability of an exciton originating at a PS II reaction centre being deexcited during transfer to PS II chlorophylls p 23 probability of an exciton originating in PS II chlorophylls being deexcited during transfer to the LHCP p 32 probability of an exciton originating in the LHCP being deexcited during transfer to PS II chlorophylls B N fraction of total PS I excitation that results from energy transfer from PS II to PS I

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CD PROPERTIES Of THE fAST-fOLDING AND SLOW-fOLDING fORMS Of UNfOLDED RIBONUCLEASE-A

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fEBS LETTERS 1982年第2期139卷 190-192页

作者： SCHMID, fX Institut für Biophysik und Physikalische Biochemie Universität Regensburg 8400 Regensburg FRG

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CHANGES IN fLUORESCENCE-SPECTRA BY NITRATE AND NITRITE IN A BLUE-GREEN-ALGA

PHOTOBIOCHEMISTRY AND PHOTOBIOPHYSICS

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PHOTOBIOCHEMISTRY AND PHOTOBIOPHYSICS 1982年第5-6期4卷 257-264页

作者： SERRANO, A RIVAS, J LOSADA, M UNIV SEVILLE FAC BIOL DEPT BIOQUIM SEVILLE SPAIN UNIV SEVILLE CSIC SEVILLE SPAIN

The effect of nitrate and nitrite on fluorescence spectra of whole cells of the filamentous blue-green alga Anabaena sp. strain 7119 was investigated under different conditions. Emission spectra of cells excited with light of 590 nm under argon atmosphere exhibit high levels of PS [photosystem] II Chl [chlorophyll] a and phycobilin fluorescence. Switching to aerobic conditions or addition, under anaerobic conditions, of either nitrate or nitrite to nitrate-grown cells induces a strong quenching of PS II Chl a fluorescence (685 nm) and a weak one of PS I Chl a (740 nm), without significantly affecting phycobilin fluorescence (66770 nm). Ammonia-grown cells, which lack the nitrate-reducing enzyme system, exhibit likewise Chl a fluorescence quenching by oxygen but are not responsive to either nitrate or nitrite. The addition of DCMU [3-(3,4-dichlorophenyl)-1,1-dimethylurea] increses Chl a fluorescence. In the presence of this inhibitor, however, neither nitrate or nitrite is able to promote its typical quenching effect. Upon excitation at different wavelengths, both nitrogenous compounds also bring about quenching of Chl a fluorescence, the excitation spectra being analogous to the absorption spectrum of phycobilins. These facts correlate Chl a fluorescence with the photochemical reactions involved in the ferredoxin-dependent enzymatic reduction of nitrate and nitrite in blue-green algae.

关键词： Chi a Chlorophyll a DCMU 3-(3,4-dichlorophenyl)-1,1-dimethyjurea f fluorescence intensity at a determined wavelength PS I Photosystem I PS II Photosyslem II

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Mitochondrial coupling factor B. Properties and role in ATP synthesis

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BBA Reviews On Bioenergetics 1982年第1期683卷 39-56页

作者： Rao Sanadi, D. Department of Cell Psychology Boston Biomedical Research Institute Boston MA 02114 20 Staniford Street United States Department of Biological Chemistry Harvard Medical School Boston MA 02115 United States

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RECONSTRUCTION Of THE CHLOROPLAST NON-CYCLIC ELECTRON-TRANSPORT PATHWAY fROM WATER TO NADP WITH 3 INTEGRAL PROTEIN COMPLEXES

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PROCEEDINGS Of THE NATIONAL ACADEMY Of SCIENCES Of THE UNITED STATES Of AMERICA-BIOLOGICAL SCIENCES 1982年第18期79卷 5494-5498页

作者： LAM, E MALKIN, R UNIV CALIF BERKELEY DIV MOLEC PLANT BIOL BERKELEY CA 94720 USA UNIV CALIF BERKELEY DEPT BIOPHYS BERKELEY CA 94720 USA

Reconstruction of photosynthetic noncyclic electron transport from water to NADP was accomplished by using 3 integral protein complexes isolated from [spinach] chloroplast thylakoid membranes, photosystems I and II and the cytochrome b6-f complex. This system has an absolute dependence on the presence of all 3 protein complexes for NADP reduction, in addition to plastocyanin, ferredoxin and ferredoxin-NADP reductase. The reconstructed system was sensitive to low concentrations of known inhibitors of noncyclic electron transport. Depletion of the Rieske fe center and bound plastoquinone from the cytochrome b6-f complex resulted in an inhibition of the photoreduction of NADP.

关键词： photosystem I photosystem II cytochrome b 6 - f

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THYLAKOID MEMBRANE-PROTEIN PHOSPHORYLATION LEADS TO A DECREASE IN CONNECTIVITY BETWEEN PHOTOSYSTEM-II REACTION CENTERS

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BIOCHIMICA ET BIOPHYSICA ACTA 1982年第3期680卷 336-342页

作者： KYLE, DJ HAWORTH, P ARNTZEN, CJ MICHIGAN STATE UNIV DOE PLANT RES LAB E LANSING MI 48824 USA

The room-temperature fluorescence induction transients from stroma-free chloroplast [pea] membranes (in the presence of 3-(3,4-dichlorophenyl)-1,1-dimethylurea) were analyzed to determine the effects of membrane protein phosphorylation on the connectivity between photosystem (PS) II centers. Chloroplast membranes which have been incubated in the light with ATP exhibit a decrease in the variable fluorescence as a function of the initial fluorescence, a shift from a sigmoidal to an exponential fluorescence induction curve and a reduced amount of the fast (.alpha.) component of the induction transient. These phenomena are completely reversible by dark incubation of the samples (leading to protein dephosphorylation). Apparently, connectivity between PS II centers is reduced as a function of thylakoid membrane protein phosphorylation. This may in turn be the mechanism which increases the amount of absorbed excitation energy available to PS I.

关键词： Membrane protein phosphorylation Reaction center Photosystem II fluorescence (Chloroplast membrane) DCMU 3-(3,4-dichlorophenyl)-1,1-dimethylurea Tricine N -tris(hydroxymethyl)methylglycine PS photosystem LHC II light-harvesting chlorophyll-protein complex of PS II Q primary stable electron acceptor of PS II Chl chlorophyll f m maximal level of fluorescence f 0 initial level of fluorescence

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MUTATION ASSAY AT THE THYMIDINE KINASE LOCUS IN DIPLOID HUMAN-LYMPHOBLASTS

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MUTATION RESEARCH 1982年第2期94卷 467-485页

作者： LIBER, HL THILLY, WG MIT DEPT NUTR & FOOD SCI GENET TOXICOL GRP CAMBRIDGE MA 02139 USA

A thymidine kinase heterozygote was isolated from a diploid human lymphoblast line which forms colonies with high efficiency in microtiter dishes. This cell line, called TK6, can be mutated from a TK+/- to TK-/- state by diverse mutagens, including ethyl methanesulfonate, butyl methanesulfonate, nitrosomethylurea, UV light, ICR-191, 4-nitroquinoline oxide, fluorodeoxyuridine, benzo[a]pyrene and aflatoxin B1. The experiments required to demonstrate the applicability of this new line in quantitative assays of mutation in human cells are reported. Mitotic recombination between the centromere and the tk locus could not be induced by either dimethylsulfoxide or phorbol-12-myristate-13-acetate.

关键词： 8AG, 8-azaguanine BMf, background mutant fraction BMS, butyl methanesulfonate CHAT, cytidine, hypoxanthine, aminoprterin, thymidine DMSO, dimethylsulfoxide f 3 TdR, trifluorothymidine HGPRT, hypoxanthine-guanine phosphoribosyl transferase Mf, mutant fraction PBS, phosphate-buffered saline PMS, post-mitochondrial supernatant R, resistant S, sensitive 6TG, 6-thioguanine THC, thymidine, hypoxanthine, cytidine TK, thymidine kinase TMP, thymidylic acid

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PROTON-TRANSPORTING URINARY EPITHELIA - REACTIVITY WITH N,N'-DICYCLOHEXYLCARBODIIMIDE

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BIOCHIMICA ET BIOPHYSICA ACTA 1982年第2期680卷 152-160页

作者： KESSLER, RJ fANESTIL, DD UNIV CALIF SAN DIEGO DEPT MED LA JOLLA CA 92093 USA

Dicyclohexylcarbodiimide (DCCD), a potent inhibitor of the f0f1[complex consisting of a section intrinsic to the membrane (f0) that functions as an H+ channel and a multi-subunit complex extrinsic to the membrane (f1) that is the catalytic (ATP hydrolase) component]-type H+-translocating ATPase, was employed to determine the possible involvement of such an ATPase in urinary acidification. Two methods were used in this approach: the reaction of [14C]DCCD with tissues involved in urinary acidification and the inhibition of ATPase activity by DCCD. Membrane components from epithelial cells of toad and turtle urinary bladder and brush borders of rabbit kidney were reacted with [14C]DCCD and analyzed by polyacrylamide gel electrophoresis both before and after extraction with organic solvents. Although a DCCD-binding component was extracted from toad and turtle bladder membranes by chloroform/methanol (2:1, vol/vol), the binding was not saturable. Analysis of this DCCD-binding component by TLC indicated that there was no ninhydrin reactivity associated with the [14C]DCCD binding. All attempts to precipitate a DCCD-binding protein were unsuccessful. Apparently, the observed DCCD binding was to phospholipid. In the 2nd type of experiment, the ATPase activity present in brush borders from rabbit kidney was partially inhibited by DCCD, but at a concentration that is over 2 orders of magnitude greater than that required for typical DCCD-sensitive ATPase. Because of the failure in finding positive evidence of a DCCD-reactive protein and from the relative insensitivity of the ATPase to DCCD, either urinary acidification may not be accomplished by a typical f0f1-type translocating ATPase, or the f0 maybe modified so that the sensitivity to DCCD was altered or lost.

关键词： DCCD H + transport f 0 f 1 -ATPase (Urinary bladder) DCCD N , N ′-dicyclohexylcarbodiimide TEMED N , N , N ′, N ′-tetramethylethylenediamine EEDQ N -ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline Mes 2-( N -morpholino)ethanesulfonic acid

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PHARMACOLOGICAL EffECTS Of 2-AMINOTETRALINS, OCTAHYDROBENZO[f]QUINOLINES AND CLONIDINE ON THE ISOLATED GUINEA-PIG ILEUM

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EUROPEAN JOURNAL Of PHARMACOLOGY 1981年第4期71卷 475-482页

作者： MAIXNER, W ARNERIC, SP ZEITHAR, MSA LECOMPTE, J VERIMER, T CANNON, JG LEE, T LONG, JP UNIV IOWA COLL MED DEPT PHARMACOL IOWA CITY IA 52242 USA UNIV IOWA COLL PHARM DIV MED CHEM & NAT PROD IOWA CITY IA 52242 USA

The ability of derivatives of 2-aminotetralins (2AT), cis- or trans-isomers of octahydrobenzo[f]quinolines (BfQ) and clonidine to modulate acetylcholine release was studied using field-stimulated guinea pig ilea (GPI). Antihistaminic and antiacetylcholine activities were determined using isolated superfused segments of GPI. Hydroxylated 2AT, BfQ and clonidine inhibited field stimulation-induced contractions through .alpha.-adrenoceptor mechanisms which were antagonized by phentolamine. The inhibition produced by nonhydroxylated 2AT was not attenuated by .alpha.-adrenoceptor antagonism. 2AT, trans-7,8-dihydro-BfQ and cis-8,9-dihydroxy-BfQ inhibited contractions induced by nicotine bitartrate using superfused GPI. Clonidine was inactive as an antinicotinic agent and there was no correlation between a compound''s ability to inhibit contractions induced by field stimulation and its antinicotinic activity. Various 2AT derivatives demonstrated weak antimuscarinic and/or antihistaminic activities on superfused ileal segments. These data demonstrate that these agents possess a spectrum of pharmacological activity.

关键词： α-Adrenoceptors Clonidine 2-Aminotetralin Octahydrobenzo[ f ]quinoline Cholinergic Antihistaminic

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EffECT Of THE NATURAL ATPASE INHIBITOR ON THE BINDING Of ADENINE-NUCLEOTIDES AND INORGANIC-PHOSPHATE TO MITOCHONDRIAL-f1-ATPASE

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BIOCHIMICA ET BIOPHYSICA ACTA 1981年第2期636卷 185-192页

作者： KLEIN, G LUNARDI, J VIGNAIS, PV CEN DEPT RECH FONDAMENTALE CNRS EQUIPE RECH 903 F-38041 GRENOBLE FRANCE

Incubation of the beef heart mitochondrial ATPase, f1 with Mg-ATP was required for the binding of the natural inhibitor, If1, to f1 to form the inactive f1-If1 complex. When f1 was incubated in the presence of [14C]ATP and MgCl2, about 2 mol 14C-labeled adenine nucleotides bound per mol of f1;the bound 14C-labeled nucleotides consisted of [14C]ADP arising from [14C]ATP hydrolysis and [14C]ATP. The 14C-labeled nucleotide binding was not prevented by If1. These data are in agreement with the idea that the formation of the f1-If1 complex requires an appropriate conformation of f1. The 14C-labeled adenine nucleotides bound to f1 following preincubation of f1 with Mg-[14C]ATP could be exchanged with added [3H]ADP or [3H]ATP. No exchange occurred between added [3H]ADP or [3H]ATP and the 14C-labeled adenine nucleotides bound to the f1-If1 complex. These data suggest that the conformation of f1 in the isolated f1-If1 complex is further modified in such a way that the bound 14C-labeled nucleotides are no longer available for exchange. 32Pi was able to bind to isolated f1 with a stoichiometry of about 1 mol of P1/mol of f1. There was no binding of 32P1 to the f1-If1 complex. Not only the nucleotides sites, but also the Pi site, are masked from interaction with external ligands in the isolated f1-If1 complex.

关键词： f 1 -ATPase Adenine nucleotide binding ATPase inhibitor (Bovine heart mitochondria) Mops 3-( N -morpholino)propanesulfonic acid

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