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ESTIMATION Of H+-TRANSLOCATION STOICHIOMETRY Of MITOCHONDRIAL ATPASE BY COMPARISON Of PROTON-MOTIVE fORCES WITH CLAMPED PHOSPHORYLATION POTENTIALS IN SUB-MITOCHONDRIAL PARTICLES

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BIOCHIMICA ET BIOPHYSICA ACTA 1982年第1期682卷 184-188页

作者： SORGATO, MC GALIAZZO, f PANATO, L fERGUSON, SJ UNIV PADUA IST CHIM BIOLI-35100 PADUAITALY UNIV BIRMINGHAM DEPT BIOCHEMBIRMINGHAM B15 2TTW MIDLANDSENGLAND

The proton-motive forces generated in submitochondrial particles by both hydrolysis of ATP and oxidation of succinate have been measured by flow dialysis and compared with the ambient phosphorylation potentials. It is concluded that three H + are translocated for each ATP molecule hydrolysed or synthesised. By utilising rat liver mitochondria respiring with β-hydroxybutyrate as a new system for regeneration of ATP from ADP and P i , phosphorylation potentials were clamped at a range of values by using mixtures of particles and mitochondria in various ratios. As the rate of ATP hydrolysis by the particles was lowered, the proton-motive force decreased only slightly except at the very lowest rates, these results paralleling earlier studies on the relation between rate of respiration-driven proton translocation and proton-motive force.

关键词： H + translocation ATPase Proton-motive force Stoichiometry Phosphorylation potential (Submitochondrial particle) Δp , proton-motive force = Δ \ ̃ gm H + f = Δψ+ 2.303RT Δ pH f , where f is the faraday constant ΔG p , phosphorylation potential = ΔG °′+ RT ln[ATP ] [ ADP][P i ] Δψ, membrane potential (in mV) ΔpH, pH gradient across the membrane Hepes, 4-(2-hydroxyethyl)-1-piperazineethanesulphonic acid EGTA, ethylene glycol bis( β -aminoethyl ether)- N , N , N ′, N ′-tetraacetic acid Ap 5 A, P 1 , P 5 -di(adenosine-5′-)pentaphosphate fCCP, carbonyl cyanide p -trifluoromethoxyphenylhydrazone

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RNA POLYMERASE-I fROM DROSOPHILA-HYDEI PUPAE - PURIfICATION AND PARTIAL CHARACTERIZATION

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fEBS LETTERS 1982年第1期142卷 7-11页

作者： GUNDELfINGER, E STEIN, H Max-Planck-Institut für Biologie Abt. Beermann Spemannstraße 34 7400 Tübingen FRG

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THE EffECT Of PROBE BINDING ON THE QUANTITATIVE-DETERMINATION Of THE PROTON-MOTIVE fORCE IN BACTERIA

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BIOCHIMICA ET BIOPHYSICA ACTA 1982年第1期681卷 85-94页

作者： LOLKEMA, JS HELLINGWERf, KJ KONINGS, WN STATE UNIV GRONINGEN DEPT MICROBIOL 9751 NN HAREN NETHERLANDS

The electrical potential across the cytoplasmic membrane of bacteria can be calculated from the distribution of the lipophilic cation tetraphenylphosphonium between the bulk phases of the medium and the cytoplasm. To determine the bulk phase concentrations, information about the binding of the probe to the cellular components is required. In de-energized cells of Rhodopseudomonas sphaeroides the binding appears to be proportional to the free probe concentration. The bulk phase concentrations can only be determined when knowledge is available about the distribution of the binding of the probe over the different cellular components. Models for binding are presented which are based on the assumption that the binding is an energy-independent process. These models allow a proper calculation of the electrical potential when the binding of the different cellular components is known.

关键词： Nonsaturable probe binding Proton-motive force quantitation Bacterial bioenergetics Tetraphenylphosphonium TPP + tetraphenylphosphonium ion TPMP + triphenylmethylphosphonium ion TPB − tetraphenylborate ion Mes 2-( N -morpholino)ethanesulphonic acid Hepes N -2-hydroxyethylpiperazine- N -2-ethanesulphonic acid. Glossary: Δ \ ̃ gm H + , proton-motive force Δψ electrical transmembrane potential difference ΔpH transmembrane H + concentration gradient C o probe concentration in the medium before adding the cells C i intracellular free probe concentration C b i intracellular bound probe concentration C cm cytoplasmic membrane probe concentration C om outer membrane probe concentration C e extracellular probe concentration V volume of the system x fractional internal volume y fractional cytoplasmic membrane volume z fractional outer membrane volume f cm ratio of fractional cytoplasmic membrane and intracellular volume f om ratio of fractional outer membrane and intracellular volume K i binding constant for binding to intracellular components K cm cytoplasmic membrane partition coefficient K om outer membrane partition coefficient k first-order proportionality constant between flux and concentration N b(f) number of bound (free) probe molecule

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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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THE PEPTIDYL-SUBSTITUENT WITHIN PEPTIDYL-TRNA INCREASES THE STABILITY Of TRANSfER-RNA MESSENGER-RNA ASSOCIATION

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fEBS LETTERS 1982年第1期142卷 125-128页

作者： HOLSCHUH, K SCHNERWITZKI, D SCHMITT, M GASSEN, HG Fachgebiet Biochemie Institut für Organische Chemie und Biochemie Technische Hochschule Darmstadt Petersenstr. 22 D-6100 Darmstadt FRG

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KIRROMYCIN-RESISTANT ELONGATION fACTOR-TU fROM WILD-TYPE Of LACTOBACILLUS-BREVIS

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fEBS LETTERS 1982年第2期146卷 322-326页

作者： WORNER, W WOLf, H Institut für Biologie II Lehrstuhl für Mikrobiologie I der Universität D-74000 Tübingen FRG

Properties of the elongation factor Tu from Lactobacillus brevis which is naturally insensitive to kirromycin are described. The protein is characterized by an unusual nucleotide-binding site with increased affinity for GTP and extreme heat stability. Ef-Tu is sensitive to pulvomycin in the assay of polyphenylalanine synthesis. However, the failure of the protein to display pulvomycin-dependent GDP-binding and GTPase activity indicates that pulvomycin action in L. brevis differs from that in E. coli.

关键词： Elongation factor Tu Lactobacillus brevis Kirromycin resistance Pulvomycin Nucleotide-binding site Heat stability Ef elongation factor Ef-Tu f nucleotide-free elongation factor Tu affices refer to the source of the protein Ec Escherichia coli Lb Lactobacillus brevis

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PROPERTIES Of ENZYME-ACTIVITIES INVOLVED IN PROTEIN PHOSPHORYLATION-DEPHOSPHORYLATION Of THYROID PLASMA-MEMBRANES

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BIOCHIMICA ET BIOPHYSICA ACTA 1982年第2期718卷 125-134页

作者： KASAI, K fIELD, JB ST LUKES EPISCOPAL HOSP BAYLOR COLL MED DEPT MED DIABET RES LAB HOUSTON TX 77030 USA

Bovine thyroid tissue exhibited cAMP-dependent and Ca2+-dependent protein kinase activities and a basal (cAMP- and Ca2+-independent) one, and phosphoprotein phosphatase activity. Although the former 2 protein kinase activities were not clearly demonstrated using endogenous protein as substrate, they were clearly shown in soluble, particulate and plasma membrane fractions using exogenous histones as substrate. The highest specific activities were in the plasma membrane. The apparent Km values of cAMP and Ca2+ for the membrane-bound protein kinase were 5 .cntdot. 10-8 M and 8.3 .cntdot. 10-4 M (in the presence of 1 mM EGTA [ethylene glycol-bis(.beta.-aminoethyl ether)N,N,N'',N''-tetraacetic acid]), respectively. The apparent Km values of Mg2+ were 7 .cntdot. 10-4 M (without cAMP and Ca2+), 5 .cntdot. 10-4 M (with cAMP) and 1.3 .cntdot. 10-3 M (with Ca2+), and those of ATP were 3.5 .cntdot. 10-5 M (with or without cAMP) and 8.5 .cntdot. 10-5 M (with Ca2+). The Ca2+-dependent protein kinase could be dissociated from the membrane by EGTA washing. The enzyme activity so released was further activated by added phospholipid (phosphatidylserine/1,3-diolein), but not by calmodulin. Phosphoprotein phosphatase activity was also clearly demonstrated in all of the fractions using 32P-labeled mixed histones as substrate. The activity was not modified by either cAMP or Ca2+, but was stimulated by a rather broad range (5-25 mM) of Mg2+ and Mn2+. NaCl and substrate concentrations also influenced the activity. Pyrophosphate, ATP, inorganic phosphate and Naf inhibited the activity in a dose-dependent manner. Trifluoperazine, chlorpromazine, dibucaine and Triton X-100 (above 0.05%, wt/vol) specifically inhibited the Ca2+-dependent protein kinase in plasma membranes. Repetitive phosphorylation of intrinsic and extrinsic proteins by the membrane-bound enzyme activities clearly showed an important co-ordination of them at the step of protein phosphorylation. These enzyme activities in plas

关键词： Phosphorylation Dephosphorylation Protein kinase (Thyroid plasma membrane) TSH thyrotropin EGTA ethylene glycol bis( β -aminoethylether)- N , N ′-tetraacetic acid PP pyrophosphate P i inorganic phosphate f fluoride

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DEVELOPMENT AND SPECTRAL CHARACTERISTICS Of EXCITATION-ENERGY TRANSfER BETWEEN THE PHOTOSYSTEMS DURING CHLOROPLAST BIOGENESIS

PHOTOBIOCHEMISTRY AND PHOTOBIOPHYSICS

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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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REQUIREMENTS fOR DIffERENT CA-2+ POOLS IN THE ACTIVATION Of RABBIT PLATELETS .1. RELEASE REACTION AND PROTEIN-PHOSPHORYLATION

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BIOCHIMICA ET BIOPHYSICA ACTA 1982年第3期714卷 492-499页

作者： SHAW, JO LYONS, RM UNIV TEXAS HLTH SCI CTR PULM DIV MED SAN ANTONIO TX 78284 USA UNIV TEXAS HLTH SCI CTR HEMATOL DIV MED SAN ANTONIO TX 78284 USA AUDIE L MURPHY MEM VET ADM HOSP SAN ANTONIO TX 78284 USA

The role of Ca2+, both extracellular and intracellular in origin, in the release reaction and protein phosphorylation in rabbit platelets stimulated with platelet activating factor (acetylglyceryl ether phosphorylcholine), thrombin or ionophore A23187 was examined. In the presence of extracellular Ca2+, 8-(N,N-diethylamino)octyl-3,4,5-trimethoxybenzoate (TMB-8), a putative antagonist of intracellular Ca2+ transport, blocked platelet activating factor-initiated serotonin release at a half-maximal inhibitor concentration of 40 .mu.M, compared to 350 .mu.M for thrombin-induced release and > 500 .mu.M for A23187-induced release. Platelet activating factor-induced phosphorylation of 2 platelet proteins of MW = 41,000 (P7P) and 20,000 (P9P) was inhibited by TMB-8, an effect which was additive to that caused by removing extracellular Ca2+. TMB-8 demonstrated only minor to nonexistent inhibitory effects on phosphorylation in thrombin- or A23187-stimulated platelets. In contrast to P9P phosphorylation, phosphorylation of P7P caused by platelet activating factor was more dependent on a TMB-8 sensitive step than on the availability of extracellular Ca2+. Experiments with buffers containing fixed concentrations of free Ca2+ revealed that both processes (release and phosphorylation), when stimulated by platelet activating factor and thrombin, had the same threshold requirement (1-3 .mu.M) for extracellular free Ca2+. Stimulation of rabbit platelets by platelet activating factor may be more dependent on a TMB-8-Activation of different intracellular processes involved in platelet secretion (such as P7P and P9P phosphorylation) may require Ca2+ from different pools.

关键词： Ca 2+ pool Activation Release reaction Protein phosphorylation (Rabbit platelet) SDS sodium dodecyl sulfate, TMB-8, 8-( N , N -diethylamino)octyl-3,4,5-trimethoxybenzoate EGTA ethylene glycol bis( β -aminoethyl ether)- N , N -tetraacetic acid Ca 2+ f free Ca 2+ concentration

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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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