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The associations of membrane systems

Journal of Electroanalytical Chemistry 1983年第C期155卷 315-333页

作者： Bourd, G.I. Martirosov, S.M. The Gamaleya Institute for Epidemiology and Microbiology Academy of Medical Sciences Russian Federation Armenian Branch of VNII Genetika Box 45 Genetika Box 45 Genetika Russian Federation

This review is devoted to the data on the intramembranal interactions of proteins for the regulation of membrane transport, of cell metabolism anf of energy transformation. first discussed are the results on H⁺ transfer via the ATPase complex f₁f₀ and the counter-transport of K⁺ in glycolysing bacteria. It is concluded that the f₁f₀ and the natural K⁺ ionophore are able to form an intramembranal binary supercomplex for the joint employment of ATP energy. Such a supercomplex operates like an ionic pump, exchanging 2 H⁺ for K⁺ and capable of both hydrolysis and synthesis of ATP with the essential decrease of energy dissipation. It is also assumed that such a system in gram-negative bacteria includes, as a third portion, a protein regulator which turns the H⁺/K⁺ exchange on and off dependent on osmotic pressure in the medium. The data on H⁺/K⁺ antiport in bacteria are also considered. In this case the possibility of the formation of another type of supercomplex formed by the proton channel f₀ and the K⁺ ionophore is suggested. Thus, the interaction of membrane proteins for the joint employment of converted energy ATP, Δμ ̄_H and Δμ ̄_K is considered. In the second part of the review the results on the cell metabolism regulation through the intramembranal interaction of some systems in bacteria are described. These regulations are performed via the mechanisms known as "inducer exclusion" and "catabolite repression". The reciprocal inhibiting effect under the interplay of PTS and lactose permease is shown. The lactose permease is assumed to be inoperative due to the interaction with E₁₁ when the latter translocates glucose (or mannose). Some experiments serve as the evidence that the catabolite repression connected with the fall in adenylate cyclase activity occurs at membrane l

关键词： DCCD N,N′-dicyclohexylcarbodiimide Δμ ̄ is the electrochemical potential difference δψ is the membrane potential f 1 f 0 is the ATPase complex for H + transport f 1 is the ATPase f 0 the proteolipid incorporated in a membrane TrkA is the system for transfer of K + Trkf is the H + /K + -exchanging system ΔpH is H + gradients Δp K is K + gradients PTS is the phosphoenolpyruvate-dependent carbohydrate phosphotransferase system PEP is phosphoenolpyruvate MG is methyl-α- d -glucopyranoside AC is adenylate cyclase M-protein is β-galactoside permease product of gene lac Y ONPG is o -nitrophenyl-β- d -galactopyranoside NEM is N-ethylmaleimide TDG is thiodigalactoside E II is the membrane component of the PTS

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A NOTE ON SCREENING REGRESSION EQUATIONS

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AMERICAN STATISTICIAN 1983年第2期37卷 152-155页

作者： fREEDMAN, DA Statistics Department University of California Berkeley CA 94720 United States

Consider developing a regression model in a context where substantive theory is weak. To focus on an extreme case, suppose that in fact there is no relationship between the dependent variable and the explanatory variables. Even so, if there are many explanatory variables, theR2will be high. If explanatory variables with smalltstatistics are dropped and the equation refitted, theR2will stay high and the overallfwill become highly significant. This is demonstrated by simulation and by asymptotic calculation.

关键词： Regression Regression f Multiple testing

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3 CATALYTIC SITES IN MITOCHONDRIAL ATPASE

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fEBS LETTERS 1983年第1期158卷 151-153页

作者： CERDAN, E CAMPO, ML LOPEZMORATALLA, N SANTIAGO, E UNIV NAVARRA DEPT BIOCHEMPAMPLONASPAIN

Kinetic data obtained after determining the hydrolytic activity of ATPase from rat liver in preparations where the enzyme had been purified, or in mitochondria, strongly suggest the existence of three different catalytic sites with different affinity for the substrate. The results obtained when measuring the ATPase activity at different substrate concentrations, and in the presence of the inhibitors KOCN or KSCN, or of the activators dinitrophenol and bicarbonate, show that the binding of these compounds to a regulatory site or sites affects in a different degree the hydrolytic activity of each catalytic site.

关键词： Mitochondrial ATPase f 1 -ATPase Catalytic site. (Rat liver)

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服棉酚者和其他原因所致的无精症患者血中促性腺激素与甾体激素的变化

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中华生殖与避孕杂志 1983年第2期 31-35页

作者：张桂元周学沄高素敏郭芝生刘国振曹坚北京计划生育科学技术研究所首都医院

本文比较了正常男子(Ⅰ组)、各种无精症患者(包括棉酚服用者。Ⅱ组)、原因不明的无精症者(Ⅲ组)以及Klinefelter 综合征患者(Ⅳ)血浆中fSH、LH、PRL、T、E和f 的变化。结果所有无精症患者的平均fSH、LH 水平明显高于Ⅰ组(P0.05)Ⅱ、Ⅲ... 详细信息

本文比较了正常男子(Ⅰ组)、各种无精症患者(包括棉酚服用者。Ⅱ组)、原因不明的无精症者(Ⅲ组)以及Klinefelter 综合征患者(Ⅳ)血浆中fSH、LH、PRL、T、E和f 的变化。结果所有无精症患者的平均fSH、LH 水平明显高于Ⅰ组(P<0.001),但PRL、T、E及f 的平均值与Ⅰ组无区别(P>0.05)Ⅱ、Ⅲ组患者fSH 水平升高者与正常者各为50%,其余各组明显高于正常。Ⅲ组的LH 及T/LH 比值仍在正常范围内,但T、E及f 的平均值升高,PRL 降低;其余各组LH 与fSH 平行升高,T 及T/LH比值明显低于Ⅰ组(P<0.001),但E、f 及PRL 则在正常范围内。本实验证实,避孕剂量的棉酚并不损害睾丸合成T 的功能。fSH 过高说明生精上皮损害过度。本文还提出了一些控制棉酚用量的客观指标。

关键词： Azoospermia Gossypol fSH LH PRL T E2 f

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STUDIES Of THE NUCLEOTIDE-BINDING SITES ON THE MITOCHONDRIAL-f1-ATPASE THROUGH THE USE Of A PHOTOACTIVABLE DERIVATIVE Of ADENYLYL IMIDODIPHOSPHATE

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BIOCHIMICA ET BIOPHYSICA ACTA 1982年第1期682卷 124-134页

作者： LUNARDI, J VIGNAIS, PV Laboratoire de Biochimie (CNRS/ERA 903 et INSERM/U.191) Départment de Recherche Fondamentale Centre d'Etudes Nucléaires 85X 38041 Grenoble cedex France

N-4-Azido-2-nitrophenyl-.gamma.-[3H]-aminobutyryl-AdoPP[NH]P (NAP4-AdoPP[NH]P) a photoactivable derivative of 5-adenylyl imidodiphosphate (AdoPP[NH]P), was synthesized. Binding of [3H]NAP4-AdoPP[NH]P to soluble ATPase from beef heart mitochondria (f1) was studied in the absence of photoirradiation, and compared to that of [3H]AdoPP[NH]P. The photoactivable derivative of AdoPP[NH]P bound to f1 with high affinity, like AdoPP[NH]P. Once [3H]NAP4-AdoPP[NH]P had bound to f1 in the dark, it could be released by AdoPP[NH]P, ADP and ATP, but not at all by NAP4 or AMP. Preincubation of f1 with unlabeled AdoPP[NH]P, ADP or ATP prevented the covalent labeling of the enzyme by [3H]NAP4-AdoPP[NH]P on photoirradiation. Photoirradiation of f1 by [3H]NAP4-AdoPP[NH]P resulted in covalent photolabeling and concomitant inactivation of the enzyme. full inactivation corresponded to the binding of .apprx. 2 mol [3H]NAP4-AdoPP[NH]P/mol f1. Photolabeling by NAP4-AdoPP[NH]P was much more efficient in the presence than in the absence of MgCl2. Bound [3H]NAP4-AdoPP[NH]P was localized on the .alpha.- and .beta.-subunits of f1. At low concentrations (< 10 .mu.M), bound [3H]NAP4-AdoPP[NH]P was predominantly localized on the .alpha.-subunit;at concentrations equal to, or greater than 75 .mu.M, .alpha.- and .beta.-subunits were equally labeled. The extent of inactivation was independent of the nature of the photolabeled subunit (.alpha. or .beta.), suggesting that each of the 2 subunits, .alpha. and .beta., is required for the activity of f1. The covalently photolabeled f1 was able to form a complex with aurovertin, as does native f1. The ADP-induced fluorescence enhancement was more severely inhibited than the fluorescence quenching caused by ATP. The percentage of inactivation of f1 was virtually the same as the percentage of inhibition of the ATP-induced fluorescence quenching, suggesting that fluorescence quenching is related to the binding of ATP to the catlytic site of f1.

关键词： Nucleotide binding f 1 -ATPase Adenylyl imidodiphosphate Photolabeling (Bovine heart mitochondria) f 1 , soluble mitochondrial ATPase from beef heart mitochondria Ado PP [NH] P , 5-adenylyl imidodiphosphate NAP 4 , N -4-azido-2-nitrophenyl- γ -aminobutyric acid NAP 4 -Ado PP [NH] P , N -4-azido-2-nitrophenyl- γ -aminobutyryl-Ado PP [NH] P NAP 4 -ADP, N -4-azido-2-nitrophenyl- γ -aminobutyryl-ADP

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BAHADUR EffICIENCY Of THE f-TEST

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JOURNAL Of STATISTICAL PLANNING AND INfERENCE 1982年第3期6卷 301-304页

作者： BARKER, L SETHURAMAN, J FLORIDA STATE UNIV DEPT STATTALLAHASSEEFL 32313

Extremal problems in large deviations of the f -statistic are considered. It is shown that the slowest rate of convergence over a specified class of distributions of the f -statistic is slower than exponential, and that the Bahadur efficiency of the f -statistic with respect to some distribution-free competitors is identically zero.

关键词： 60f10 62G10 Ansari-Bradley Statistic Bahadur Efficiency f -statistic Large deviations Moses Ranklike Statistic

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THROMBOXANE-B2 UPTAKE AND METABOLISM IN ISOLATED PERfUSED LUNG IDENTIfICATION AND COMPARISON WITH PROSTAGLANDIN-f2-ALPHA

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BIOCHIMICA ET BIOPHYSICA ACTA 1982年第2期712卷 315-325页

作者： ROBINSON, C PEERS, SH WADDELL, KA BLAIR, IA HOULT, JRS UNIV LONDON KINGS COLL DEPT PHARMACOL LONDON WC2R 2LS ENGLAND

Thromboxane B2 was metabolized in isolated perfused guinea-pig lungs to a product identified by negative ion chemical ionization mass spectrometry as 13,14-dihydro-15-ketothromboxane B2. Conversion was measured by radio TLC and was greater in guinea pig than rat lungs (29.1 vs. 13.8% at 10 ng/ml), but similar in lungs from normal and sensitized guinea pigs. Thromboxane B2 metabolism was less than that of prostaglandin ***. but, like it, was prevented at ***. C and reduced by cycloheximide pretreatment. Tissue to medium ratio in perfused guinea pig lungs was 3.4 for thromboxane B2, but 0.2 for inulin (showing that thromboxane B2 is accumulated within the lung) and was altered after experimental manipulations. Neither lung slices, crude homogenates, cytosolic and microsomal fractions nor purified prostaglandin 15-hydroxydehydrogenase metabolized thromboxane B2 in vitro, although prostaglandin ***. was extensively inactivated. Quantitative partition coefficient and albumin-binding data confirm that thromboxane B2 lacks prominent lipophilicity, implying that cellular uptake in lung must be carrier-mediated. Thromboxane B2 is a substrate for pulmonary degradation which may form a route for the biological inactivation of thromboxane A2. Its resistance to prostaglandin 15-hydroxydehydrogenase as conventionally tested remains paradoxical and is discussed.

关键词： Prostaglandin f 2 α Thromboxane B 2 (Lung)

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ELECTROGENIC PROTON TRANSLOCATION BY THE CHLOROPLAST CYTOCHROME-B6/f COMPLEX RECONSTITUTED INTO PHOSPHOLIPID-VESICLES

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fEBS LETTERS 1982年第2期149卷 211-216页

作者： HURT, EC HAUSKA, G SHAHAK, Y UNIV REGENSBURG INST BOT D-8400 REGENSBURG FED REP GER WEIZMANN INST SCI DEPT BIOCHEM IL-76100 REHOVOT ISRAEL

When the cytochrome b 6 / f complex from chloroplasts is incorporated into liposomes, reduction of external plastocyanin by plastoquinol is stimulated under uncoupling conditions. An extra H + /e − is ejected from the vesicles during the reaction, in addition to the scalar proton liberated from plastoquinol. This is stimulated by valinomycin/K + and abolished under uncoupling conditions. furthermore, the formation of a membrane potential during the reaction, negative inside the vesicles, is observed with the help of carbocyanine dyes. We conclude that the cytochrome b 6 / f complex, like the cytochrome bc 1 from mitochondria, functions as an electrogenic proton translocator.

关键词： Cytochrome b 6 / f complex Chloroplast Electron transport Proton translocation Membrane potential Carbocyanine Antimycin A diO-C 5 -(3) 3,3'-dipentyloxacarbocyanine diS-(C 3 -(5) 3,3'-dipropylthiadicarbocyanine DNP-INT 2-iodo-6-isopropyl-3-methyl-2', 4,4'-trinitrodiphenyl ether fCCP carbonyl cyanide p -trifluoromethoxy-phenylhydrazone HEPES N -2-hydroxyethylpiperazine- N '-ethanesulfonic acid

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THE 695 NM fLUORESCENCE (f-695) Of CHLOROPLASTS AT LOW-TEMPERATURE IS EMITTED fROM THE PRIMARY ACCEPTOR Of PHOTOSYSTEM-II

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fEBS LETTERS 1982年第1期147卷 16-20页

作者： BRETON, J Service de Biophysique Département de Biologie CEN Saclay 91191 Gif-Sur-Yvette France

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SUBUNIT EQUIVALENCE IN ESCHERICHIA-COLI AND BOVINE HEART MITOCHONDRIAL f1f0 ATPASES

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fEBS LETTERS 1982年第2期146卷 393-396页

作者： WALKER, JE RUNSWICK, MJ SARASTE, M Laboratory of Molecular Biology The MRC Centre Hills Road Cambridge CB2 2QH England

f 1 -ATPases from bovine mitochondria and Escherichia coli both contain 5 subunits named α, β, γ, δ and ε. Sequence analysis shows that the δ subunits are not related, nor are the ε subunits. The counterpart of mitochondrial δ is bacterial ε. The subunit equivalent to bacterial δ is mitochondrial oligomycin sensitivity conferral protein.

关键词： f 1 f 0 -ATPase, of bovine heart mitochondria f 1 f 0 -ATPase, of Escherichia coli Subunit α, β homology Subunit δ, ε, non-equivalence

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