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METABOLISM Of 2-AMINO-3-METHYLIMIDAZO[4,5-f]QUINOLINE (IQ) AND 2-AMINO-3,4-DIMETHYLIMIDAZO[4,5-f]QUINOLINE (MEIQ) IN SUSPENSIONS Of ISOLATED RAT-LIVER CELLS

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TOXICOLOGY IN VITRO 1987年第4期1卷 175-181页

作者： HOLME, JA ALEXANDER, J BECHER, G TRYGG, B Department of Toxicology National Institute of Public Health Geitmyrsveien 75 N-0462 Oslo 4 Norway.

Suspensions of rat-liver cells metabolized (14)C-labelled 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) and 2-amino-3,4-dimethylimidazo[4,5-f]quinoline (MeIQ) to metabolites that were ethyl acetate extractable, water soluble or covalently bound to macromolecules. The major ethyl acetate extractable metabolite(s) had a retention time on the high-performance liquid chromatograph (HPLC), an ultraviolet spectrum and an R(f) value on the thin-layer chromatograph that corresponded to those of the N-acetylated derivative. Relatively more of this metabolite was formed from MeIQ than from IQ. In contrast, IQ was more easily converted to water-soluble metabolites than was MeIQ. The amount of covalently bound metabolite(s) found with MeIQ as test substance was larger than that found with IQ. No major increase in the ethyl acetate-extractable metabolites was obtained after incubation of the aqueous phase with beta-glucuronidase or aryl sulphatase in comparison with untreated controls. HPLC analysis showed that after acid hydrolysis of the water-soluble metabolites, about 55 and 20% of the hydrolysed metabolites had retention times that were the same as those of IQ and MeIQ, respectively. The ratio between covalently bound (activated) metabolites and water-soluble (detoxified) metabolites was larger for MeIQ than for IQ. from these data, one would expect MeIQ to be more potent than IQ as a liver carcinogen in male rats.

关键词： AcIQ N -acetyl-2-amino-3-methylimidazo[4,5- f ]quinoline AcMeIQ N -acetyl-2-amino-3,4-dimethylimidazo[4,5- f ]quinoline DMSO dimethylsulphoxide EGTA ethylene glycol bis-(β-aminoethyl ether) N , N , N ′, N ′-tetraacetic acid HPLC high-pressure liquid chromatography IQ 2-amino-3-methylimidazo[4,5- f ]quinoline MeIQ 2-amino-3,4-dimethylimidazo[4,5- f ]quinoline

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METABOLISM Of PROSTAGLANDIN-f1ALPHA BY RAT STOMACH

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BIOCHIMICA ET BIOPHYSICA ACTA 1970年第2期218卷 288-+页

作者： PACEASCIAK, C MORAWSKA, K WOLfE, LS Donner Laboratory of Experimental Neurochemistry Montreal Neurological Institute Mcuill University MontrealCanada

1.1. Prostaglandin f1α was shown to be converted into two metabolites by a supernatant fraction of rat stomach. These were shown to be 15-keto-prostaglandin f1α and dihydro-15-keto-prostaglandin f1α.2.2. The elucidation of the structures of these compounds was based on their Chromatographie properties, sodium borohydride and sodium borodeuteride derivatives, and mass spectrometry of their trimethylsilyl derivatives.3.3. No metabolism was found in the particulate fractions (10000 × g, or 100000 × g) of this tissue.4.4. These observations indicate that the metabolism of prostaglandins in rat stomach occurs by the prostaglandin 15-hydroxydehydrogenase pathway ratlier than by β-oxidation.

关键词： prostaglandin f 1α for 9α, 11α, 15(S)-trihydroxyprost-13-enoic acid prostaglandin f 2α for 9α, 11α, 15(S)-trihydroxyprosta-5, 13-dienoic acid PCMB p chloromercuribenzoate TMSi trimethylsilyl

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KINETIC-ANALYSIS Of PROTON TRANSLOCATION CATALYZED BY f0f1 ATPASE

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fEBS LETTERS 1988年第2期234卷 455-458页

作者： MUNEYUKI, E HIRATA, H JICHI MED SCH DEPT BIOCHEMMINAMIKAWACHITOCHIGI 32904JAPAN UNIV TOKYO FAC SCIDEPT BIOCHEM & BIOPHYSBUNKYO KUTOKYO 113JAPAN

Kinetic analysis of both proton translocating and steady-state ATP hydrolytic activities catalyzed by f0f1 ATPase in submitochondrial particles were carried out over an ATP concentration range of 1-2000 microM. The results were examined in relation to the prediction based on the alternate binding change model proposed by Gresser et al. [(1982) J. Biol. Chem. 257, 12030-12038] in which energy transduction occurs only at the tri-site catalytic cycle. The present results essentially contrast with the model and rather indicate that if the alternate binding mechanism holds for the ATP hydrolytic reaction, the proton translocation should be coupled to at least both bi-site and tri-site cycles.

关键词： f 0 f 1 -ATPase Proton translocation Alternate binding change model Negative cooperativity (Submitochondrial particle) SMP, submitochondrial particle ANS, 8-anilino-naphthalene-1-sulfonate E D , an enzyme which binds ADP and P i E DT , an enzyme which binds ATP, ADP and P i E DTD , an enzyme which binds two ADPs, P i s and ATP E DTD , the energized form of E DTD

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H-1-NMR STUDIES ON NUCLEOTIDE BINDING TO THE CATALYTIC SITES Of BOVINE MITOCHONDRIAL f1-ATPASE

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fEBS LETTERS 1988年第1期242卷 178-182页

作者： GARIN, J VIGNAIS, PV GRONENBORN, AM CLORE, GM GAO, Z BAEUERLEIN, E NIDDKD CHEM PHYS LABBETHESDAMD 20892 MAX PLANCK INST BIOCHEM MEMBRANBIOCHEM ABTD-8033 MARTINSRIEDFED REP GER

The conformation of adenine nucleotides bound to bovine mitochondrial f 1 -ATPase was investigated using transfer nuclear Overhauser enhancement measurements. It is shown that all nucleotides investigated adopt a predominantly anti conformation when bound to the catalytic sites. furthermore, the experiment suggests that 8-azido-ADP and 8-azido-ATP, which are predominantly in the syn conformation in solution, are in the anti conformation when bound to f 1 catalytic sites.

关键词： f 1 -ATPase Nucleotide Bound conformation NOE transferred AdoPP(NH)P, adenosine 5′-[β,γ-imido]triphosphate NOE, nuclear Overhauser enhancement TRNOE, transferred nuclear Overhauser enhancement

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THE COMPLEX Of MITOCHONDRIAL f1-ATPASE WITH THE NATURAL INHIBITOR PROTEIN IS UNABLE TO CATALYZE SINGLE-SITE ATP HYDROLYSIS

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fEBS LETTERS 1988年第1-2期230卷 163-166页

作者： KALASHNIKOVA, TY MILGROM, YM POSTANOGOVA, NV MOSCOW STATE UNIV AN BELOZERSKY LAB MOLEC BIOL & BIOORGAN CHEMMOSCOW 119899USSR

Interaction of mitochondrial f 1 -ATPase with the isolated natural inhibitor protein resulting in the inhibition of multi-site ATP hydrolysis is accompanied by the loss of activity at low ATP concentrations when single-site hydrolysis should occur. Catalytic site occupancy by [ 14 C]nucleotides in f 1 -ATPase during steady-state [ 14 C]ATP hydrolysis, which is saturated in parallel with single-site catalysis, is prevented after blocking the enzyme with the inhibitor protein.

关键词： f 1 -ATPase Inhibitor protein Single-site catalysis IP, natural inhibitor protein of mitochondrial f 1 -ATPase BSA, bovine serum albumin

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INCREASE IN CELL-SURfACE N-ACETYLGLUCOSAMINIDE BETA-(1-]4)GALACTOSYLTRANSfERASE ACTIVITY WITH RETINOIC ACID-INDUCED DIffERENTIATION Of f9 EMBRYONAL CARCINOMA-CELLS

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fEBS LETTERS 1984年第2期168卷 222-226页

作者： NAKHASI, HL NAGARAJAN, L ANDERSON, WB NCI TUMOR IMMUNOL & BIOL LABBETHESDAMD 20205

Exposure of f9 cells to all-trans-retinoic acid over a period of 6 days resulted in 4-fold induction of cell surface N-acetylglucosaminide beta (1----4)galactosyltransferase (GT) activity. The retinoic acid-induced GT activity was further enhanced by treatment of the cells with 8-bromo cyclic AMP. The ability of retinoic acid alone, or retinoic acid in combination with 8-bromo cyclic AMP, to induce GT activity was inhibited by both actinomycin D and cycloheximide. These findings indicate that the induction of galactosyltransferase activity noted with differentiation of f9 cells involves de novo synthesis of new enzyme protein.

关键词： f 9 cell Retinoic acid 8-Bromo cyclic AMP Galactosyltransferase activity Differentiation De novo synthesis

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DIETARY CIS-fATTY ACIDS THAT INCREASE PROTEIN f1 PHOSPHORYLATION ENHANCE SPATIAL MEMORY

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BRAIN RESEARCH 1989年第2期505卷 302-305页

作者： WONG, KL MURAKAMI, K ROUTTENBERG, A NORTHWESTERN UNIV CRESAP NEUROSCI LAB 2021 SHERIDAN RD ROOM 311 EVANSTON IL 60201 USA

Activation of protein kinase C (PKC) facilitates long-term potentiation (LTP), a model of memory, and increases its substrate protein f1 (aka GAP43) phosphorylation in direct relation to synaptic enhancement. Unsaturated fatty acids (c-fAs) which activate purified PKC, when injected into hippocampus, enhance LTP. To determine if dietary c-fAs could alter memory itself as well as brain PKC substrate (f1) metabolism, rats were maintained for 10 weeks on fatty diets enriched in mono-unsaturated oleic acid (OA: 20% olive oil, w/w), or a mono- and di-unsaturated mixture of oleate/linoleate (O/L: 20% corn oil), or a saturated fatty acid diet of laurate/myristate (L/M;20% hydrogenated coconut oil). The O/L diet group was superior to the OA and L/M groups in spatial memory performance after the first two weeks of acquisition and in later achievement of criterion performance. The O/L diet had a significantly higher hippocampal protein f1 in vitro phosphorylation than in both the OA and L/M in trained and non-trained animals. Significantly, animals that made made fewer errors showed higher f1 phosphorylation (r = 0.70). Diet both increases brain PKC substrate phosphorylation and enhances maze learning, confirming the feasibility of enhancing learning and memory by dietary regimens derived from basic neurochemical studies of synaptic plasticity.

关键词： cis -fatty acid f 1 -phosphorylation Spatial memory Protein kinase C Long-term potentiation GAP 43

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THERMAL INACTIVATION Of ELECTRON-TRANSPORT fUNCTIONS AND f0f1-ATPASE ACTIVITIES

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BIOCHIMICA ET BIOPHYSICA ACTA 1987年第1期894卷 16-28页

作者： TOMITA, M KNOX, BE TSONG, TY JOHNS HOPKINS UNIV SCH MED DEPT BIOL CHEM BALTIMORE MD 21205 USA

Bovine heart submitochondrial particles in suspension were heated at a designated temperature for 3 min, then cooled for biochemical assays at ***.C. By enzyme activity measurements and polarographic assay of oxygen consumption, it is shown that the thermal denaturation of the respiratory chain takes place in at least four stages and each stage is irreversible. The first stage occurs at 51.0 .+-. ***.C, with the inactivation of NADH-linked respiration, ATP-driven reverse electron transport, f0f1 catalyzed ATP/Pi exchange, NADH and succinate-driven ATP synthesis. The second stage occurs at 56.0 .+-. ***.C, with the inactivation of succinate-linked proton pumping and respiration. The third stage occurs at 59.0 .+-. ***.C, with the inactivation of electron transfer from cytochrome c to cytochrome oxidase and ATP-dependent proton pumping. The ATP hydrolysis activity of f0f1 persists to 61.0 .+-. ***.C. An additional transition, detectable by differential scanning calorimetry, occurring around 70.0 .+-. ***.C, is probably associated with thermal denaturation of cytochrome c and other stable membrane proteins. In the presence of either mitochondrial matrix fluid or 2 mM mercaptoethanol, all five stages give rise to endothermic effects, with the absorption of approx. 25 J/g protein. Under aerobic conditions, however, the first four transitions become strongly exothermic and release a total of approx. 105 J/g protein. Solubilized and reconstituted f0f1 vesicles also exhibit different inactivation temperatures for the ATP/Pi exchange, proton pumping and ATP hydrolysis activities. The first two activities are abolished at 49.0 .+-. ***.C, but the latter at 58.0 .+-. ***.C. Differential scanning calorimetry also detects biphasic transitions of f0f1, with similar temperatures of denaturation (49.0 and ***.C). from these and other results presented in this communication, the following is concluded. (1) A selective in

关键词： ATPase, f 0 f 1 - Electron transport chain Thermal denaturation (Bovine heart mitochondrion) Hepes 4-(2-hydroxyethyl)-1-piperazineethane-sulfonic acid Tricine N -[2-hydroxy-1,1-bis(hydroxymethyl)-ethyl]glycine P i inorganic phosphate DCCD N , N ′-dicyclohexylcarbodiimide DSC differential scanning microcalorimetry fCCP carbonylcyanide p -trifluoromethoxyphenylhydrazone

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STUDIES ON KINASE-CONTROLLED STATE TRANSITIONS IN PHOTOSYSTEM-II AND B6f MUTANTS fROM CHLAMYDOMONAS-REINHARDTII WHICH LACK QUINONE-BINDING PROTEINS

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BIOCHIMICA ET BIOPHYSICA ACTA 1988年第1期933卷 85-94页

作者： WOLLMAN, fA LEMAIRE, C Service de Photosynthèse Institut de Biologie Physico-Chimique ParisFrance

We have studied kinase-dependent state transitions in vivo using photosyntheic mutants from the green alga Chlamydomonas reinhardtii lacking in quinone-binding proteins. The aim of our study was to identify proteins involved in the plastoquinone-dependent activation of the LHC-kinase. Whereas mutants totally devoid of the quinone-binding subunits D1 and D2 of Photosystem II showed unaltered state transitions, mutants lacking the b6f complexes were incapable of state transitions. These mutants were blocked in State 1, which is indicative of either the absence of the LHC-kinase responsible for the regulation, or of the loss of a component responsible for the activation of this enzyme. These two hypotheses are discussed in light of (i) the patterns of phosphorylation of the thylakoid membrane proteins observed in the b6f mutants and (ii) the characteristics of the kinase activities recovered from their thylakoids.

关键词： LHC-kinase b 6 f complex State 1-State 2 transition Plastoquinone pool, oxidized/reduced ( C. reinhardtii ) LHC light-harvesting chlorophyll ab protein complex PS Photosystem Cf coupling factor PQ plastoquinone f max maximal fluorescence level PC plastocyanin fe-S iron-sulfur centre TMBZ 3,3,5,5′-tetramethylbenzidine DBMIB 2,5-dibromo-3-methyl-6-isopropyl- p -benzoquinone PMSf phenylmethylsulphonyl fluoride NQNO 2- n -nonyl-4-hydroxyquinoline N -oxide DNP-INT dinitrophenyl ether iodonitrothymol Hepes 4-(2-hydroxyethyl)-1-piperazineethanesulphonic acid

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THE PURIfICATION Of CYTOCHROME-f AND PLASTOCYANIN USING AffINITY-CHROMATOGRAPHY

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BIOCHIMICA ET BIOPHYSICA ACTA 1987年第2期894卷 327-331页

作者： MOLNAR, SA ANDERSON, GP GROSS, EL Department of Biochemistry The Ohio State University Columbus OH U.S.A.

Both plastocyanin and cytochrome f were purified using a combination of affinity chromatography together with established methods. Plastocyanin was partially purified using the method of Davis and San Pietro (Anal. Biochem. 95 (1979) 254–259), after which it was further purified using a column of cytochrome c covalently attached to Sepharose 4B. The affinity column was prepared using the method of Godinot and Gautheron (Methods Enzymol. 54 (1979) 112–114). The final purity index ratio ( A 278 A 597 ) was less than 1.2, which is equal to that obtained using the more expensive fPLC procedure (Anderson, G.P., Sanderson, D.G., Lee, C.H., Durell, S., Anderson, L.B. and Gross, E.L. (1987) Biochim. Biophys. Acta 894, issue 3). Cytochrome f was partially purified using a modification of the method of Matazaki et al. (Plant Cell. Physiol. 16 (1975) 237–246) and bound to an affinity column of plastocyanin covalently attached to Sepharose 4B. Cytochrome f purified using this procedure had a purity index ratio ( A 554.5 A 277 ) of 1.2. Both proteins are tyrosine proteins containing no tryptophan residues. After the affinity chromatography step, the fluorescence emission spectrum of either plastocyanin or cytochrome f was typical of a tyrosine protein free from tryptophan contamination.

关键词： Cytochrome f Plastocyanin Cytochrome c Protein-protein interaction Affinity chromatography CM-Sephadex carboxymethyl-Sephadex fPLC fast protein liquid chromatography PC-Sepharose plastocyanin covalently attached to Sepharose 4B

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