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EVIDENCE fOR THE EXISTENCE Of [2fE-2S] AS WELL AS [4fE-4S] CLUSTERS AMONG fA,fB AND fX - IMPLICATIONS fOR THE STRUCTURE Of THE PHOTOSYSTEM-I REACTION CENTER

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BIOCHIMICA ET BIOPHYSICA ACTA 1987年第1期891卷 94-98页

作者： GOLBECK, JH MCDERMOTT, AE JONES, WK KURTZ, DM PORTLAND STATE UNIV DEPT CHEM PORTLAND OR 97207 USA UNIV CALIF BERKELEY CHEM BIODYNAM LAB BERKELEY CA 94720 USA IOWA STATE UNIV SCI & TECHNOL DEPT CHEM AMES IA 50011 USA UNIV GEORGIA DEPT CHEM ATHENS GA 30602 USA

Core extrusion of the bound iron-sulfur centers from spinach Photosystem I showed the presence of [2fe-2S] clusters as well as [4fe-4S] clusters among fA, fB and fX. Extrusion of the iron-sulfur ensemble was not quantitative;however, the presence of [2fe-2S] clusters correlated with higher concentration of unfolding solvent. Since fX is highly resistant to denaturation, and since fA and fB are known to contain [4fe-4S] clusters, the [2fe-2S] clusters are assigned to fX. The presence of [2fe-2S] clusters in Photosystem I has significance in the structure and organization of fX on the reaction center. Since four cysteinyl ligands are assumed to hold an iron-sulfur cluster, a Photosystem I subunit may consist of two approx. 64-kDa proteins bridged by a single [2fe-2S] cluster. The complete reaction center would consist of two subunits positioned so that two [2fe-2S] clusters are in magnetic interaction, thereby constituting fX.

关键词： fe-S cluster Photosystem I ESR NMR Reaction center structure PS I Photosystem I Chl chlorophyll HMPA hexamethylphosphoramide DMSO dimethylsulfoxide R f SH p -trifluoromethylbenzenethiol

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CLONAL SPECIfICITY ANALYSIS Of MITOGEN-ACTIVATED MURINE LYMPHOBLASTS-T

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IMMUNOBIOLOGY 1987年第5期175卷 431-446页

作者： HEEG, K STEEG, C KABELITZ, D REIMANN, J WAGNER, H Department of Medical Microbiology and Immunology University of Ulm Federal Republic of Germany.

We have determined the frequencies and specificities of MHC-reactive and MHC-restricted cytotoxic T lymphocyte precursors (CTL-p) in mitogen (ConA)-activated splenocytes of normal unprimed mice. The limiting dilution (LD) system supported the growth of one out of three Lyt2+ T cell blasts. The generated CTL-populations lysed blast cell targets specifically as determined by split well analyses. MHC-gene product expression was necessary for lysis to occur, since MHC-negative f9 teratocarcinoma cells were not lysed. The frequency determinations and split well analysis revealed: 1) equally high numbers (.apprx. 1/100) of CTL-p that generated specific allo-MHC or self-MHC reactive CTL populations, 2) high frequencies of CTL-p which recognized hapten (TNP) or minor H (MH)-antigens in the context of self MHC or allo-MHC determinants. The results are discussed with respect to antigen, restriction and receptor specificities of mitogen-activated unprimed T cell blasts.

关键词： chi2 value for chi2 ConA concanavalin A CTL cytotoxic T lymphocyte CTL-p cytotoxic T lymphocyte precursor(s) f frequency fCS fetal calf serum IL 2 interleukin 2 LD limiting dilution LDA limiting dilution analysis α-MM methyl-α-D-mannoside p probability for single-hit kinetics PEC peritoneal exudate cells PHA phytohemagglutinin PTL proliferating T lymphocytes TNP- trinitrophenyl- 95 % CL 95 % confidence limit

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HORMONAL-REGULATION Of 6-PHOSPHOfRUCTO-2-KINASE fRUCTOSE-2,6-BISPHOSPHATASE - KINETIC-MODELS

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fEBS LETTERS 1987年第2期217卷 212-215页

作者： GOLDSTEIN, BN IVANOVA, AN ACAD SCI USSR INST CHEM PHYSBOROKUSSR

A graphical method to reveal the so-called 'critical fragments' in schemes of biochemical systems is considered. These fragments produce multiple steady states or self-oscillations in systems. As an example, the bifunctional enzyme, 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase, regulated by glucagon through enzyme phosphorylation, is discussed. It is shown that this enzyme may act as a metabolic switching mechanism in discontinuous or oscillatory regimes, depending on the specific structure of its kinetic scheme. The boundaries of concentrational and parameter domains for these critical phenomena are also predicted.

关键词： Bifunctional enzyme Graph-theoretical method Glucagon switching signal Critical phenomenon E 1 , 6-phosphofructo-2-kinase E 2 , fructose-2,6-bisphosphatase S 1 , fructose 6-phosphate S 2 , fructose 2,6-bisphosphate f 1 , cAMP-dependent protein kinase f 2 , phosphoprotein phosphatase

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ISOLATION AND IDENTIfICATION Of A 4TH SUBUNIT IN THE MEMBRANE PART Of THE CHLOROPLAST ATP-SYNTHASE

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fEBS LETTERS 1987年第1期218卷 27-30页

作者： fROMME, P GRABER, P SALNIKOW, J TECH UNIV BERLIN INST BIOCHEM & MOLEC BIOL D-1000 BERLIN 10 GERMANY

The subunit composition of highly active purified ATP-synthase from chloroplasts, Cf 0 f 1 , was investigated by SDS gel electrophoresis. An additional subunit of Cf 0 , was detected with an apparent molecular mass of 20 kDa. It is stained weakly with Coomassie blue but very strongly with silver. This subunit was isolated on a preparative SDS gel and the N-terminal amino acid sequence analyzed. It shows that the 20 kDa protein is identical with the protein encoded by the spinach chloroplast gene atp I, called subunit IV [(1986) Mol. Genet. 203, 117–128]. However, in comparison to the gene-derived sequence, the first 18 amino acids are missing, indicating N-terminal processing.

关键词： Chloroplast ATP-synthase Cf 0 f 1 Cf 0 subunit Amino acid sequence Cf 0 f 1 , proton translocating ATP-synthase from chloroplasts HPLC, high-pressure liquid chromatography

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ACTIVATION Of MUTAGENIC AND CARCINOGENIC HETEROCYCLIC AMINES BY S-9 fROM THE LIVER Of A RHESUS-MONKEY

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TOXICOLOGY IN VITRO 1987年第1期1卷 45-48页

作者： ISHIDA, Y NEGISHI, C UMEMOTO, A fUJITA, Y SATO, S SUGIMURA, T NATL CANC CTR RES INST1-1 TSUKIJI 5 CHOMECHUO KUTOKYO 104JAPAN NCI DIV CANC ETIOLBETHESDAMD 20892

The mutagenicity of a series of heterocyclic amines isolated from various cooked foods and from pyrolysates of amino acids and protein was assayed in Salmonella typhimurium TA98 in the presence of an S-9 fraction prepared from the liver of an untreated male rhesus monkey (Macaca mulatta). All the compounds showed mutagenicity, which ranged from 1 to 2500 revertants/mug chemical/mg S-9 protein. 2-Amino-3,4-dimethylimidazo[4,5-f]quinoline (MeIQ) showed the highest specific mutagenic activity, followed by 2-amino-3,7,8-trimethylimidazo[4,5-f]quinoxaline (7,8-DiMeIQx), 2-amino-3-methylimidazo[4,5-f]quinoline (IQ), 2-amino-3,4,8-trimethylimidazo[4,5-f]quinoxaline 4,8-DiMeIQx, 3-amino-1-methyl-5H-pyrido[4,3-b]indole (Trp-P-2), 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole (Trp-P-1), 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx), 2-amino-6-methyldipyrido[1,2-a:3',2'-d]imidazole (Glu-P-1) and 2-amino-3-methyl-9H-pyrido[2,3-b]indole (MeAalphaC). 2-Amino-9H-pyrido[2,3-b]indole (AalphaC) and 2-aminodipyrido[1,2-a:3',2'-d]imidazole (Glu-P-2) also showed definite but weak mutagenicity. When compared with previously reported data, these specific mutagenic activities were very close to those of some heterocyclic amines assayed with the S-9 of human liver, slightly lower than those determined with the S-9 of untreated rat liver and much lower than those determined with S-9 from the liver of the untreated hamster or mouse. Most of the heterocyclic amines tested in this experiment have shown carcinogenicity in mice and rats. The experimental results now reported suggest the possible carcinogenicity of these heterocyclic amines in primates as well, including humans.

关键词： AαC 2-Amino-9 H -pyrido[2,3- b ]indole 4,8-DiMeIQx 2-amino-3,4,8-trimethylimidazo[4,5- f ]quinoxaline 7,8-DiMeIQx 2-amino-3,7,8-trimethylimidazo[4,5- f ]quinoxaline Glu-P-1 2-amino-6-methyldi-pyrido[1,2- a :3′,2′- d ]imidazole Glu-P-2 2-aminodi-pyrido[1,2- a :3′,2′- d ]imidazole IQ 2-amino-3-methyl-imidazo[4,5- f ]quinoline MeAαC 2-amino-3-methyl-9 H -pyrido[2,3- b ]indole MeIQ 2-amino-3,4-dimethyl-imidazo[4,5- f ]quinoline MeIQx 2-amino-3,8-dimethyl-imidazo[4,5- f ]quinoxaline Trp-P-1 3-amino-1,4-dimethyl-5 H -pyrido[4,3- b ]indole Trp-P-2 3-amino-1-methyl-5 H -pyrido[4,3- b ]indole

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Inhaled anaesthetics and filter-circuit. Mathematical model and Basic computer programme

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Annales francaises d'anesthesie et de reanimation 1987年第5期6卷 401-407页

作者： Deriaz, H. Duranteau, R. Lienhart, A. Département d'Anesthésie-Réanimation Hôpital Saint-Antoine F 75012 Paris 184 rue du Faubourg Saint-Antoine France Département d'Anesthésie-Réanimation Hôpital Lariboisière 75010 Paris France

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BONDING ANOMALIES IN THE RARE-EARTH SESQUIOXIDES

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JOURNAL Of PHYSICS AND CHEMISTRY Of SOLIDS 1987年第5期48卷 475-479页

作者： URBAN, MW CORNILSEN, BC MICHIGAN TECHNOL UNIV DEPT CHEM & CHEM ENGNHOUGHTONMI 49931

Raman and IR vibrational spectra of C-type rare earth sesquioxides exhibit anomalous wavenumber decreases for europium ( f 6 ) and ytterbium ( f 13 ) oxide which have not been previously reported. Because of the large shifts observed for the Raman spectra, the IR band positions have been re-examined. Smaller, but definite decreases have been observed in the IR spectra as well. Scatter in the literature data had obscured these anomalies. The anomalies correlate with thermodynamic properties and indicate weaker bonding for these two oxides. It is suggested that these anomalies are caused by electron-phonon interaction, involving low-lying f -states which are below the fermi level for europium and ytterbium. Therefore, these data provide another example of a system in which 4 f electronic structure significantly influences chemical bonding. We suggest that it is due to the presence of the unique, low-lying electronic energy levels in these two elements, and not simply the result of the number of f electrons (half-full or full). Literature results suggest the anomalies are not due to “mixed valence” for Eu 2 O 3 and Yb 2 O 3 ; however, further research is needed to explain the origin more completely. Raman band positions are reported for the first time for several of the oxides.

关键词： Raman spectra infrared spectra rare earths C-type sesquioxides europium ( f 6 ) anomaly ytterbium ( f 13 ) anomaly electron-phonon coupling f -electron configurations

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URACIL DNA GLYCOSYLASE ACTIVITY IN HUMAN ACUTE-LEUKEMIA

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LEUKEMIA RESEARCH 1987年第6期11卷 557-563页

作者： KOISTINEN, P EEROLA, E VILPO, JA UNIV OULU DEPT INTERNAL MED SF-90220 OULU FINLAND UNIV OULU DEPT CLIN CHEM MOLEC HEMATOL LAB SF-90220 OULU FINLAND UNIV TURKU DEPT MED MICROBIOL SF-20500 TURKU 50 FINLAND

The expression of the DNA excision repair enzyme uracil-DNA glycosylase was investigated in bone marrow and peripheral samples from seven patients with acute lymphoblastic leukemia (ALL), from 17 patients with acute non-lymphocytic leukemia (ANLL), and from one patient with chronic granulocytic leukemia (CGL) in blast crisis. In addition, uracil-DNA glycosylase activities were determined in nine human leukemia/lymphoma cell lines. There was a clear correlation between the percentage of blast cells and the enzyme activity, when mononuclear cell fractions from patient samples were analysed. The following uracil-DNA glycosylase activities were recorded (mean .+-. S.D., number of samples): ALL = 45.6 .+-. 14.8 U/mg of protein, N = 10;ANLL = 41.1 .+-. 13.8 U/mg of protein, N = 22;CGL (blast crisis) = 44.7 U/mg of protein. The uracil-DNA glycosylase activity in nine human leukemia/lymphoma cell lines ranged from 35.2 to 66.0 U/mg of protein, and no striking differences were observed between the T-ALL, B-ALL, null cell ALL or myeloid lines. Similarily, the various biological features, such as the common ALL surface antigen, the terminal deoxynucleotidyl transferase enzyme, the subtype of leukemia, chromosomal aberrations, or previous chemotherapy, did not apparently affect the expression of uracil-DNA glycosylase. We propose that the integrity of the genetic information is well protected by uracil-DNA glycosylase in different forms of leukemia, including cases with a low proportion of S-phase blasts, as assessed by flow cytometry in the present work. When compared to the activities in benign hematopoietic progenitor cells, studied previously in this laboratory, no big differences between the benign and malignant hematopoiesis were demonstrated. Hence, it is unlikely that selectivity of chemotherapy towards malignant vs benign hematopoietic growth could be based on the enzyme uracil-DNA glycosylase.

关键词： Uracil-DNA glycosylase acute leukemia DNA repair ALL acute lymphoblastic leukemia ANLL acute non-lymphocytic leukemia CGL chronic granulocytic leukemia CALLA common all surface antigen TdT terminal deoxynucleotidyl transferase enzyme PBS phosphate buffered saline (pH 7.4) f female M male PB peripheral blood BM bone marrow fAB french-American-British dTMP deoxythymidine monophosphate dUMP deoxyuridine monophosphate dCMP deoxycytidine monophosphate

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ENERGY-DEPENDENT K+ UPTAKE AND H+-K+ EXCHANGE IN SALMONELLA-TYPHIMURIUM

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BIOELECTROCHEMISTRY AND BIOENERGETICS 1987年第2期17卷 183-192页

作者： TRCHOUNIAN, AA TERNIKOGOSSIAN, VA MARTIROSOV, SM Department of Biophysics Biological Faculty of Yerevan State University 375049 Yerevan U.S.S.R.

Anaerobically grown Salmonella typhimurium LT-2 has a proton-motive force .DELTA..hivin..mu.H+/f equal to 150 mV. In alkaline media containing glucose and moderate K+ activity, the bacteria take up K+ in two steps, the first of which occurs with Km = 2.1 mM and vmax = 0.44 mM g-1 min-1. The K+ uptake is sensitive to external osmolarity. The first step of K+ uptake takes place as an H+-K+ exchange with a stable ratio of DCC-sensitive ion fluxes, 2 H+ from a cell being exchanged for one K+ of the medium. This exchange is not observed for the unc mutant of S. typhimurium TH-31 with unfunctional H+-ATPase. Aerobically grown S. typhimurium LT-2 takes up K+ in one step via the Trk-like system and manifests an H+-K+ exchange with an unstable ratio of DCC-sensitive ion fluxes. Q110 has the same value of 1.8 for both H+ and K+ fluxes in anaerobically grown cells and differs from these fluxes in aerobically grown ones. The K+ distribution between a cell and the medium in anaerobically grown bacteria is higher than that in aerobically grown one. The potassium equilibrium potential is much higher than the measured Um in anaerobically grown cells and equal to Um in aerobically grown ones. Transport of H+ and K+ with a stable ratio of DCC-sensitive ion fluxes in anaerobically grown S. typhimurium is assumed to take place via a mechanism which involves the structural association of H+-ATPase f0 .cntdot. f1 and the Trk-like system (S.M. Martirosov and A.A. Trchounian, Bioelectrochem. Bioenerg, 11 (1983) 29;G. I. Bourd and S. M. Martirosov, Bioelectrochem. Bioenerg., 10 (1983) 315), whereas the same transport systems operate separatively in aerobically grown cells. The Trk-like system in aerobically grown bacteria works as the K+-ionophore using Um as the energy source for K+ accumulation.

关键词： f 0 ·f 1 and Trk are the systems for ATP-dependent transfer of H + and K + respectively f 1 is ATPase, f 0 proteolipid, the Trk system refers to E. coli cells Δ μ H + is the transmembrane difference of electrochemical potentials for H + f the faraday constant U m the membrane potential ΔpH is the pH difference DCC is N,N′-dicyclohexylcarbodiimide TPP + is tetraphenylphosphonium cation EDTA is ethylendiaminetetraacetic acid K m and ν max are the Michaelis constant and the maximal rate respectively Q 10 is Van't Hoffs temperature coefficient.

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H+-K+ EXCHANGE AND DELTA-MU-BAR-H+ IN LACTOBACILLUS-SALIVARIUS

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BIOELECTROCHEMISTRY AND BIOENERGETICS 1987年第3期17卷 503-508页

作者： TRCHOUNIAN, AA OGANDJANIAN, ES MARTIROSOV, SM Department of Biophysics Biological Faculty of Yerevan State University 375049 Yerevan U.S.S.R.

Lactobacillus salivarius maintains a high concentration difference of K+ between a cell and the medium equal to 2 .times. 103, the appropriate Nernst''s equilibrium potential being essentially larger than the measured .DELTA..vphi.. At the range of external pH from 5.0 to 7.6 the bacteria has an alkaline internal pH, .DELTA..vphi. near 100-150 mV and a proton-motive force equal to 150-170 mV. L. salivarius uptakes K+ with km 3.3 mM and vmax 0.3 mmol g-1 min-1. The K+ is accumulated through the DCC-sensitive H+/K+ exchange with a raio of 2 H+/K+. The magnitudes of the fluxes of H+ and K+ during this exchange are noticeably altered after changes in external pH, K+ activity and temperature, but nevertheless the 2 H+/K+ ratio remains unchanged. The 2 H+/K+ exchange is blocked by protonophores and arsenate. The DCC-sensitive ATPase activity of bacterial protoplasts is increased in the presence of K+ in the medium. It is supposed that the exchange of 2 H+ from a cell for one K+ of the medium results from the association of the H+-ATPase with K+-ionophore and such a binary supercomplex operates as the H+-K+ pump in the membranes of anaerobic L. salivarius.

关键词： f 1 ·f 0 is H + -ATPase complex Trk is the system of K + uptake in E. coli [1,7] Δ μ H + = the difference of electrochemical potentials for H + , f = faraday's constant Δφ = transmembrane potential ΔpH is pH difference DCC is N,N′-dicyclohexylcarbodiimide CCCP is carbonylcyanide- m -chlorphenylhydrazine: TPP + is tetraphenylphosphonium cation EDTA is ethylenediaminetetraacetic acid k m and ν max are the Michaelis constant and maximal rate respectively P i is inorganic phosphorus p is the criterion of authenticity.

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