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Andrew Robson, Amanda Andrews, Robert Dawson Scott, Andrew Pierce, DJM, Sheila Rhodes, Dr James Briggs, David Rose, Michael Davidoff, R. Sumeray, Christine Seib, James Ducker, Clive Davis, Geoffrey Bernstein, Laurie Edmans, Elizabeth Judge, Carl Mortished, Patrick Kidd, James Hider, Jeremy Whittle, Kevin Eason, Abdul Kadir Hussain, Geoff Brown, Susie Bicknell, Tim Albone and David Sanderson, Robert Gore-Langton, Dominic Walsh, Dan Sabbagh Media Editor, Dan Sabbagh, Nicholas Blanford, Stephen Farrell, Alan Hamilton, Alan Klier, Charles Bremner, Jonathan Richards, Stefanie Marsh, Shirley English and David Lister, Russell Kempson, Terence Kealey, Gary Duncan Economics Editor, Oliver Kay, John Westerby, Jeffrey Lee, Tom Baldwin, Jill Sherman Whitehall Editor, Louisa Barnett, John Hopkins Golf Correspondent, B. R. J. Simpson, Edward Gorman Motor Racing Correspondent, David Powell Athletics Correspondent, Gerald Morgan, Adam Sage, Matt Hughes, Dr Tanya Byron, Marcus Binney Architecture Correspondent, Peter Wheeldon, Peta Bee, Bronwen Maddox, Valerie Elliott and Sam Lister, Christopher Martin-Jenkins Chief Cricket Correspondent, Damian Whitworth, Paul Simons, Andrew Harris, William Rees-Mogg, Nick Szczepanik, James Bone and Daniel McGrory, Tim Hames, Craig Lord, Dominic Maxwell, Janet Turner, Alan Tayler, Caitlin Moran, Paul Cripps, Anthony Cutler, Alexandra Blair and Sukhraj Randhawa, Richard Beeston Diplomatic Editor, Rajeev Syal, Elizabeth Vice, David Sanderson, Jack Malvern Arts Reporter, Jamie Whyte, Lewis Smith Environment Reporter, Chris Ayres, Eric Brown, Michael Horsnell, Carl Mortished International Business Editor, Dr Thomas Stuttaford, Simon Amstell, Stephen Gardiner, Leo Lewis, David Powell, Richard Morrison, George Hoffman, Owen Slot, Brian Clarke Fishing Correspondent, David Robertson, Joe Bolger, Dr Patricia Henshall, Kathy Orton,

... trading places Trust me, I'm an acetyl-transferase. How to find virtue in an enzyme Meanwhile ...

2006 - Gale Group | TDA

Artigo Acesso aberto Revisado por pares

Hiroshi Nagano, H Zalkin, Ellen J. Henderson,

... pathway, anthranilate synthetase-anthranilate 5-phosphoribosylpyrophosphate phosphoribosyltransferase (PR transferase), and with the anthranilate synthetase Component I protein ... dependent anthranilate synthetase activities of anthranilate synthetase-PR transferase. DON inactivates glutamine-dependent anthranilate synthetase activity of ... of anthranilate synthetase activity of anthranilate synthetase-PR transferase by DON is dependent upon the substrate chorismate, ... the aggregate, anthranilate synthetase Component I and PR transferase, can be separated by disc gel electrophoresis in ...

Tópico(s): Enzyme Structure and Function

1970 - Elsevier BV | Journal of Biological Chemistry

Artigo Acesso aberto Revisado por pares

Ronald S. Goor, Elizabeth S. Maxwell,

... ribose moiety of NAD is transferred to aminoacyl transferase II, resulting in the concomitant loss of transferase activity in protein synthesis. Some general characteristics of ... of the reaction is proportional to toxin, aminoacyl transferase II, and NAD concentrations, but, in the presence ... is dependent only on the amount of aminoacyl transferase II present. ADP ribosylation occurs at all temperatures ... with a maximum at 20°. The adenosine diphosphoribosylaminoacyl transferase II bond is stable to heating at 90° ...

Tópico(s): Neonatal Health and Biochemistry

1970 - Elsevier BV | Journal of Biological Chemistry

Artigo Acesso aberto Revisado por pares

Ellen J. Henderson, H Zalkin, Lian Hua Hwang,

Abstract Anthranilate 5-phosphoribosylpyrophosphate phosphoribosyltransferase (PR transferase) catalyzes the second specific reaction in the tryptophan biosynthetic pathway. This protein is aggregated to anthranilate synthetase Component I, which functions in ... Salmonella tryphimurium. Catalytically active preparations of unaggregated PR transferase had a molecular weight of approximately 87,000. ... polypeptide chain. Aggregated and unaggregated forms of PR transferase activity were inhibited by tryptophan and required saturating ...

Tópico(s): Folate and B Vitamins Research

1970 - Elsevier BV | Journal of Biological Chemistry

Artigo Acesso aberto Revisado por pares

Fumio Ibuki, Kivie Moldave,

Abstract Transferase I loses activity slowly when incubated in Tris buffer with MgCl2 and NH4Cl at 37°; when GTP ... the presence of GTP, aminoacyl-transfer RNA protects transferase I completely against inactivation while, in the absence ... the rapid nucleotide-stimulated loss of activity of transferase I. Whereas transferase I is protected against inactivation when aminoacyl-transfer ... on aminoacyl transfer or on the activity of transferase I. When ribosomes, transferase I, GTP, and aminoacyl-transfer RNA are incubated, ...

Tópico(s): RNA and protein synthesis mechanisms

1968 - Elsevier BV | Journal of Biological Chemistry

Artigo Revisado por pares

Arpi Hagopian, H.Bruce Bosmann, E.H. Eylar,

... The distribution and properties of three glycoprotein:glycosyl transferases within these membranes was determined. A multienzyme group of glycosyl transferases, which is involved in the assembly of the ... of this group include a polypeptidyl:N-acetylgalactosaminyl transferase that catalyzes the synthesis of a proteincarbohydrate linkage and a glycoprotein:galactosyl transferase that attaches galactose to N-acetylglucosamine residues during ... carbohydrate units of the glycoprotein. The N-acetylgalactosaminyl transferase, for example, was purified 45–50-fold, representing ...

Tópico(s): Carbohydrate Chemistry and Synthesis

1968 - Elsevier BV | Archives of Biochemistry and Biophysics

Artigo Acesso aberto Revisado por pares

Lawrence Skogerson, Kivie Moldave,

Abstract When ribosomes are incubated with transferase II, guanosine triphosphate, and a sulfhydryl compound, ribosomes can be isolated which carry out aminoacyl transfer in the presence of transferase I, 14C-aminoacyl transfer ribonucleic acid, and GTP, but in the absence of added transferase II. The initial rate of aminoacyl transfer with isolated ribosome-transferase II complex is markedly stimulated compared to that with nonpreincubated ribosomes. Binding of transferase II to ribosomes can be obtained with GTP ...

Tópico(s): Radiopharmaceutical Chemistry and Applications

1968 - Elsevier BV | Journal of Biological Chemistry

Artigo Acesso aberto Revisado por pares

Thomas A. Tedesco, William J. Mellman,

... was maximal and least variable, the ratio of transferase to galactokinase correlated well with the transferase genotypes of the original tissue donors. Leukocyte transferase: galactokinase ratios gave a similar distribution pattern. Whereas transferase activity in both fibroblasts and leukocytes was similar, ... strains tested had similar galactokinase activity regardless of transferase genotype.The kinetic properties of fibroblast galactokinase were ... intermediates have no effect. There was no detectable transferase activity in eight galactosemic (Gt(G)/Gt(G)) ...

Tópico(s): Metabolism and Genetic Disorders

1969 - American Society for Clinical Investigation | Journal of Clinical Investigation

Artigo

Jack Siler, Kivie Moldave,

... at low Mg2+ concentrations, in the presence of transferase I (aminoacyl-tRNA-binding factor), GTP, and poly ... Mg2+ concentrations, binding requires poly U but not transferase I and GTP. N-Acetylphenylalanyl-tRNA is bound ... but the reaction is not affected by GTP, transferase I or other soluble proteins. The N-acetylphenylalanyl- ... to ribosomes does not react with puromycin, unless transferase II and GTP are present or are added ... ribosomes are isolated from binding-reaction mixtures containing transferase II and GTP, the reaction with puromycin is ...

Tópico(s): DNA and Nucleic Acid Chemistry

1969 - Elsevier BV | Biochimica et Biophysica Acta (BBA) - Nucleic Acids and Protein Synthesis

Artigo Revisado por pares

Sarah S. Martin, H.Bruce Bosmann,

... the transfer from UDP-glucose (mitochodrial glycoprotein: glycosyl transferase system) and GDP-mannose (mitochondrial glycoprotein: mannosyl transferase system) were studied in detail. Activity of these transferase systems was dependent on structural intactness of the ... the mitochondrial glycoprotein: glycosyl and mitochondrial glycoprotein: mannosyl transferase systems Ca2+ and Mg2+ were the best activators ... The catalytic activity of the mitochondrial glycoprtein: glucosyl transferase system had a sharp pH dependence with the ...

Tópico(s): ATP Synthase and ATPases Research

1971 - Elsevier BV | Biochimica et Biophysica Acta (BBA) - General Subjects

Artigo

George R. Girgis, D.McEwen Nicholls,

... with excess poly(U) and a control liver transferase preparation. 2. The pH 5 supernatant fraction was ... increase was associated with aminoacyl-tRNA binding factor (transferase I) activity. 4. Kidney aminoacyl-tRNA binding factor (transferase I) was separated from peptidyl-tRNA translocation factor (transferase II) by Sephadex G-200. The incorporation of [ ... tRNA into peptide was measured using fractions containing transferase I obtained from control and nephrotic kidney and supplemented with control liver transferase II factor. Similarly fractions containing transferase II obtained ...

Tópico(s): Biochemical and Molecular Research

1971 - Elsevier BV | Biochimica et Biophysica Acta (BBA) - Nucleic Acids and Protein Synthesis

Artigo Revisado por pares

Claramma M. Chacko, Joe C. Christian, Henry L. Nadler,

... an unstable form of galactose-1-phosphate uridyl transferase in apatient with clinical galactosemia is described. Galactose-1-phosphate uridyl transferase activity in the red blood cells was approximately ... and isotonic phosphate buffer. Galactose-1-phosphate uridyl transferase from the mother and maternal grandmother demonstrated storge ... the presence of an additional allele at the transferase locus, which may result in a new variant ... an unstable form of galactose-1-phosphate uridyl transferase in apatient with clinical galactosemia is described. Galactose- ...

Tópico(s): Neonatal Health and Biochemistry

1971 - Elsevier BV | The Journal of Pediatrics

Artigo Revisado por pares

Pierre Broquet, Pierre Louisot,

... level. Three transglycosylation activities have been located : Mannosyl-transferase, galactosyl-transferase and N-acetyl-glucosaminyl-transferase. After cellular fractionation according to Whittaker's technique ... forms. It thus appears that N-acetyl glucosaminyl-transferase is homogeneously present in all neurone membranes. On the contrary, galactosyl-transferase and even more mannosyl-transferase are chiefly located on the synaptic vesicles. Nous ... activités de transglycosylation ont été localisées : la mannosyl-transférase, la galactosyl-transférase et la N-acétyl-glucosaminyl- ...

Tópico(s): Barrier Structure and Function Studies

1971 - Elsevier BV | Biochimie

Artigo Revisado por pares

H B Bosmann,

Abstract— Four glycoprotein:glycosyl transferases (a fetuin: N ‐acetylglucosaminyl transferase; a bovine submaxillary mucin: N ‐acetylgalactosaminyl transferase; a collagen: glucosyl transferase and an orosomucoid: galactosyl transferase) were purified 34‐, 45‐, 37‐ and 47‐fold, ... were ineffective as acceptors. The fetuin: N ‐acetylglucosaminyl transferase functioned only with fetuin minus N ‐acetylneuraminic acid, ... N ‐acetylglucosamine; the bovine submaxillary mucin: N ‐ acetylgalactosaminyl transferase with bovine submaxillary much minus N ‐acetylneuraminic acid ...

Tópico(s): Carbohydrate Chemistry and Synthesis

1972 - Wiley | Journal of Neurochemistry

Artigo

W.M. Watkins,

... Leur sérum contient un taux normal de la transférase de type A1. Ces résultats permettent de conclure ... niveau de la cellule. L'absence de la transférase sérique de type H, chez les sujets « para ... On peut espérer ce résultat si toute la transférase provient de tissus autres que le tissu hématopoiétique. ... produisant cet antigène. L'étude des taux de transférases A et H dans le plasma de sept ... pH 6 et qui ressemble donc à une transférase de type A2. Deux autres ont une activité ... de 9,6 et ainsi ressemble à une transférase de type A1 (pH et pI). Le gène ...

Tópico(s): Carbohydrate Chemistry and Synthesis

1978 - Elsevier BV | Revue Franç aise de Transfusion et Immuno-hé matologie

Artigo Acesso aberto Revisado por pares

Barbara F. Hales, Valerie Jaeger, Allen H. Neims,

The glutathione S-transferases that were purified to homogeneity from liver cytosol have overlapping but distinct substrate specificities and different isoelectric points. This ... preparative electrofocusing to compare the composition of the transferases in liver and kidney cytosol. Hepatic cytosol from ... focusing on Sephadex columns into five peaks of transferase activity, each with characteristic substrate specificity. The first four peaks of transferase activity (in order of decreasing basicity) are identified ...

Tópico(s): Drug Transport and Resistance Mechanisms

1978 - Portland Press | Biochemical Journal

Artigo Acesso aberto

Peter Dimroth, Rosemarie Loyal, Hermann Eggerer,

... thio‐acyl carrier protein: citrate acyl carrier protein transferase but is shown to be also an acetyl‐CoA: citrate CoA‐transferase. 2. The enzyme catalyzes an exchange of acetyl ... was thus unequivocally shown to be a CoA‐transferase. 4. The catalytic efficiency of the enzyme in ... reaction is similar to that of other CoA‐transferases. It was concluded that the transferase subunit of citrate lyase and the classical CoA‐transferases could belong to one family to enzymes. 5. ... comparison of the mechanism of action of the transferase subunit of citrate lyase with that established for ...

Tópico(s): Protein purification and stability

1977 - Wiley | European Journal of Biochemistry

Artigo Revisado por pares

Kenji Usui, Jun-ichi FUKAMI, Takashi Shishido,

Several glutathione S-transferases which catalyze the conjugation of reduced glutathione with organophosphorus triesters were separated from fat bodies of adult female American cockroaches, Periplaneta americana (L.). Two transferases (I, V) were active on diazinon and three transferases (II, III, IV) were active on methyl parathion. The transferase (I) active on the pyrimidinyl moiety of diazinon was distinguishable from the other transferases on the O-methyl portion of methyl parathion, ...

Tópico(s): Genomics, phytochemicals, and oxidative stress

1977 - Elsevier BV | Pesticide Biochemistry and Physiology

Artigo Acesso aberto Revisado por pares

Ann M. Benson, Paul Talalay, James H. Keen, William B. Jakoby,

... for this enzymatic activity with the glutathione S-transferases (RX:glutathione R-transferase, EC 2.5.1.18) that conjugate glutathione ... steroid isomerase is associated principally with the major transferase (B), which is also known as ligandin, and ... number of carcinogens. Other rat liver-glutathione S-transferase species are far less active in the steroid ... more uniformly distributed among the five glutathione S-transferases that have been described. Steroid isomerization differs fundamentally from other reactions promoted by glutathione S-transferases in that glutathione is not consumed in the ...

Tópico(s): Pharmacogenetics and Drug Metabolism

1977 - National Academy of Sciences | Proceedings of the National Academy of Sciences

Artigo Acesso aberto Revisado por pares

Kathleen E. Gregoire, Irving Goldschneider, Randall W. Barton, F.J. Bollum,

... of bone marrow cells that contains terminal deoxynucleotidyl transferase (DNA nucleotidylexotransferase; nucleosidetriphosphate:DNA deoxynucleotidylexotransferase, EC 2.7. ... using affinity-column-purified antibody to homogeneous calf transferase. The transferase-positive cells comprise approximately 1.8% of bone marrow cells. Correcting the specific activity of terminal transferase in total bone marrow cells (0.21 units per 10 8 cells) for the percentage of transferase-positive bone marrow cells (1.8%) gives 11. ...

Tópico(s): Chronic Lymphocytic Leukemia Research

1977 - National Academy of Sciences | Proceedings of the National Academy of Sciences

Artigo Revisado por pares

Hasan Mukhtar, John R. Bend,

Glutathione S-transferase activity was determined in rat, rabbit, and guinea pig serum using styrene 7,8-oxide (SO) and benzo ( ... Of the species tested, rat had the highest transferase activity (62.5 and 3.2 nmol/min/ ... and rabbit had the lowest activity. Glutathione S-transferase activity was 60% higher in serum from male ... 1-chloro-2,4-dinitrobenzene (DNCB). Glutathione S-transferase activity was also determined in rat serum during ... and 4-day-old animals had barely detectable transferase activity. Activity increased with age and reached a ...

Tópico(s): Genomics, phytochemicals, and oxidative stress

1977 - Elsevier BV | Life Sciences

Artigo Acesso aberto

Neil Kaplowitz, G Clifton, J Kuhlenkamp, John D. Wallin,

Renal and hepatic GSH (reduced glutathione) S-transferase were compared with respect to substrate and inhibitory kinetics and hormonal influences in vivo. An example of each of five classes of substrates ( ... identical elution volume was found for all the transferase activities. Close correspondence in Km values was found for aryl, epoxide- and alkyl-transferase activities, with only the aralkyl activity significantly lower ... inhibitors of renal aryl-, aralkyl-, epoxide- and alkyl-transferase activities and inhibited renal alkene activity. Close correspondence ...

Tópico(s): Pharmacogenetics and Drug Metabolism

1976 - Portland Press | Biochemical Journal

Artigo Acesso aberto Revisado por pares

Adrian J. Ryan, Margaret O. James, Zvi Ben‐Zvi, F. C. P. Law, John R. Bend,

... 14C–styrene oxide as substrate, specific glutathione S-transferase and epoxide hydrase activities were determined in subcellular ... Rat and guinea pig had higher glutathione S-transferase activity in both liver and kidney than rabbit. Rat testis also had appreciable glutathione S-transferase activity. The perinatal development of epoxide hydrase and glutathione S-transferase was followed in liver and several extrahepatic tissues ... in both species. Epoxide hydrase and glutathione S-transferases developed at different rates in each organ, demonstrating ...

Tópico(s): Glutathione

1976 - National Institute of Environmental Health Sciences | Environmental Health Perspectives

Artigo Acesso aberto

Barbara F. Hales, Allen H. Neims,

... male Sprague-Dawley rats of hepatic glutathione S-transferase B (ligandin) in relation to the other glutathione S-transferases is described. The concentration of glutathione S-transferase B in 1-day-old male rats is ... by substrate specificity or immunologically, the proportion of transferase B relative to the other glutathione S-transferases is high during the first week after birth. At this age, 67.5% of the transferase activity towards 1-chloro-2,4-dinitrobenzene is ...

Tópico(s): Pharmacogenetics and Drug Metabolism

1976 - Portland Press | Biochemical Journal

Artigo Acesso aberto Revisado por pares

Patrick C. Kung, Paul Gottlieb, David Baltimore,

Mouse antisera against calf terminal deoxynucleotidyltransferase (terminal transferase) have been prepared. The sera have been used to characterize terminal transferase both by studying inhibition of enzyme activity and by developing a competition radioimmunoassay using highly purified 125I-labeled terminal transferase. By either assay, anti-terminal transferase serum did not cross-react significantly with calf ... of Moloney mouse leukemia virus. The calf terminal transferase did, however, share cross-reactive but not identical ...

Tópico(s): RNA Research and Splicing

1976 - Elsevier BV | Journal of Biological Chemistry

Artigo

E. Christ-Hazelhof, D.H. Nugteren, D. A. van Dorp,

... acid binding sites of serum albumin. Glutathione-S-transferases, in the presence of glutathione, convert the endoperoxide ... The prostaglandin D/E-ratio depends on the transferase used. The known rat liver transferases give mainly prostaglandin F2α and E2, but a new transferase in sheep lung was discovered which gives rise ... of prostaglandin F2α and D2. The sheep lung transferase was purified to homogeneity. Two iso-enzymes with identical enzymic activity were obtained. The major component (transferase SL 2, an iso-enzyme of glutathione-S- ...

Tópico(s): Pharmacogenetics and Drug Metabolism

1976 - Elsevier BV | Biochimica et Biophysica Acta (BBA) - Lipids and Lipid Metabolism

Artigo Acesso aberto

Barbara F. Hales, Allen H. Neims,

The glutathione S-transferases are a group of proteins with overlapping substrate specificities and ligand-binding capacities. This report examines certain approaches to the measurement of transferase B (ligandin) in the rat liver. The ratio ... indication of the relative proportions of the various transferases present in 100 000 g supernatants. The fraction ... towards 1-chloro-2,4-dinitrobenzene, due to transferase B, was best measured by immunoprecipitation with anti-(transferase B). Male rat liver exhibited three times more ...

Tópico(s): Pharmacogenetics and Drug Metabolism

1976 - Portland Press | Biochemical Journal

Artigo Revisado por pares

William H. Habig, M. Pabst, William B. Jakoby,

Glutathione S-transferase AA from rat liver was purified to apparent homogeneity as judged by gel filtration and gel electrofocusing. The ... and glutathione as substrates. The catalytic properties of transferase AA are very similar to those of transferase B although the two proteins differ in their ... and in their immunological properties. When mixtures of transferase AA with other purified glutathione S-transferases were denatured in 6 m guanidine hydrochloride and ... the presence of each of the known glutathione transferases.

Tópico(s): Genomics, phytochemicals, and oxidative stress

1976 - Elsevier BV | Archives of Biochemistry and Biophysics

Artigo Acesso aberto

P. Greenwell, R.J. Harris, Robert H. Symons,

... are in the active centre for the peptidyl transferase function of the ribosome. The affinity label as ... C in the “fragment reaction” assay of peptidyl transferase was only about 10% as efficient as puromycin, ... C led to irreversible inactivation of the peptidyl transferase activity (pH optimum 8.8) and extensive covalent ... chloramphenicol, an A′‐site‐specific inhibitor of peptidyl transferase. The chloramphenicol‐insensitive affinity labelling, designated nonspecific, was ... affinity labelling with the percentage inactivation of peptidyl transferase revealed a linear correlation between the two quantities, ...

Tópico(s): Peptidase Inhibition and Analysis

1974 - Wiley | European Journal of Biochemistry