Aminoacyl Transfer Ribonucleic Acid Synthetases Research Articles

Regulation of synthesis of the aminoacyl-transfer ribonucleic acid synthetases for the branched-chain amino acids of Escherichia coli.

The regulation of synthesis of valyl-, leucyl-, and isoleucyl-transfer ribonucleic acid (tRNA) synthetases was examined in strains of Escherichia coli and Salmonella typhimurium. When valine and isoleucine were limiting growth, the rate of formation of valyl-tRNA synthetase was derepressed about sixfold; addition of these amino acids caused repression of synthesis of this enzyme. The rate of synthesis of the isoleucyl- and leucyl-tRNA synthetases was derepressed only during growth restriction by the cognate amino acid. Restoration of the respective amino acid to these derepressed cultures caused repression of synthesis of the aminoacyl-tRNA synthetase, despite the resumption of the wild-type growth rate.

Streptomycin-suppressible lethal mutations in Escherichia coli.

Forty-one mutants have been isolated which require streptomycin for growth on complete medium. These streptomycin-suppressible lethal mutations are located randomly around the Escherichia coli genetic map; during growth in liquid culture, they exhibit a variety of responses to the removal of streptomycin as judged by turbidity, cell morphology, and macromolecular synthesis. In particular, some mutants are primarily affected in protein or ribonucleic acid (RNA) synthesis (or both), one in deoxyribonucleic acid synthesis, and two in lipid synthesis. Ten mutants affected in protein synthesis were examined for the activities of all twenty aminoacyl-transfer RNA synthetases, and three were found to have altered glutamyl-transfer RNA synthetase activities. The advantages of this method for isolating a wide variety of conditional lethal mutants are discussed.

Amino acid control over deoxyribonucleic acid synthesis in Escherichia coli infected with T-even bacteriophage.

Starvation for a required amino acid of normal or RC(str)Escherichia coli infected with T-even phages arrests further synthesis of phage deoxyribonucleic acid (DNA). This amino acid control over phage DNA synthesis does not occur in RC(rel)E. coli mutants. Heat inactivation of a temperature-sensitive aminoacyl-transfer ribonucleic acid (RNA) synthetase similarly causes an arrest of phage DNA synthesis in infected cells of RC(str) phenotype but not in cells of RC(rel) phenotype. Inhibition of phage DNA synthesis in amino acid-starved RC(str) host cells can be reversed by addition of chloramphenicol to the culture. Thus, the general features of amino acid control over T-even phage DNA synthesis are entirely analogous to those known for amino acid control over net RNA synthesis of uninfected bacteria. This analogy shows that the bacterial rel locus controls a wider range of macromolecular syntheses than had been previously thought.

Specificity of aminoacyl transfer ribonucleic acid synthetases from Escherichia coli K12.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSpecificity of aminoacyl transfer ribonucleic acid synthetases from Escherichia coli K12Masatoshi Kondo and Carl R. WoeseCite this: Biochemistry 1969, 8, 10, 4177–4182Publication Date (Print):October 1, 1969Publication History Published online1 May 2002Published inissue 1 October 1969https://doi.org/10.1021/bi00838a040RIGHTS & PERMISSIONSArticle Views32Altmetric-Citations12LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (649 KB) Get e-Alerts Get e-Alerts

Aminoacyl transfer ribonucleic acid synthetases from cell-free extract of Plasmodium berghei.

Aminoacyl transfer ribonucleic acid synthetases for leucine tyrosine, histidine, valine, proline, threonine, and lysine were obtainnned from cell-free extract of Plasmodium berghei. The leucyl-tRNA synthetase cane charge tRNA from liver or Escherichia coli with leucine-c(14), liver tRNA being a better substrate. The amount of aminoacylation increses linerly with respect to the quantity of tRNA added from either source and is dependent on the amount of enzyme added. The rate of aminoacylation is constant for 10 minutes and then decreases. It is enhanced by polyvinylsulfate. One-tenth millimoler pyrimethamine, hydroxystilbamidine, quinacrine, and acriflavine inhibited the formation of C(14)-valyl-tRNA. Species specificity between tRNA and its charging enzyme with respect to the recognition site is discussed.

Nucleotide sequence of Escherichia coli tyrosine transfer ribonucleic acid.

The nucleotide sequence of one of the Escherichia coli tyrosine-transfer ribonucleic acids was determined in order to compare its sequence with that of yeast tyrosine-transfer ribonucleic acid. Forty-four positions of both transfer ribonucleic acids are occupied by the same nucleotides if they are arranged in the manner shown here. The information obtained suggests that the conformation of transfer ribonucleic acid molecules may be a greater contributing factor than a specific nucleotide sequence in the interaction of transfer ribonucleic acid with its corresponding aminoacyl-transfer ribonucleic acid synthetase.

Properties of transfer ribonucleic acid and aminoacyl transfer ribonucleic acid synthetases from an extremely halophilic bacterium.

Properties of transfer ribonucleic acid and aminoacyl transfer ribonucleic acid synthetases from an extremely halophilic bacterium.

The Divergence in Reactivity of Aminoacyl Transfer Ribonucleic Acid Synthetases of Escherichia coli with Hydroxylamine

Abstract Fourteen partially purified Escherichia coli aminoacyl transfer ribonucleic acid synthetases were tested for their rates of amino acid hydroxamate formation relative to the rates of aminoacyl-tRNA formation. Three groups of reactivity were observed: tyrosyl-, phenylalanyl-, tryptophanyl-, and methionyl-tRNA synthetases catalyze hydroxamate formation at rates comparable to those for aminoacyl-tRNA formation; with lysyl-, alanyl-, isoleucyl-, glycyl-, cysteinyl-, leucyl-, seryl-, and valyl-tRNA synthetases, the relative rates of hydroxamate formation progressively decrease; and glutaminyl- and threonyl-tRNA synthetases do not catalyze hydroxamate formation. In an unfractionated enzyme extract, threonine hydroxamate forms, but this is totally accounted for by the mistaken activation of threonine by the valyl-tRNA synthetase. Purified threonyl-tRNA synthetase catalyzes hydroxamate formation only when tRNA is present, by catalyzing the formation of threonyl-tRNA, which reacts nonenzymatically with hydroxylamine. The mammalian threonyl-tRNA synthetase also fails to catalyze formation of threonine hydroxamate from amino acid and ATP.

Effect of polynucleotides on aminoacyl transfer ribonucleic acid synthetases: III. Inhibition of glutamyl transfer ribonucleic acid synthetase by natural polynucleotides

The inhibitory effects of several natural polynucleotides on the formation of glutamyl-tRNA by purified rat liver glutamyl-tRNA synthetase were investigated. Yeast and Escherichia coli tRNA's, which were inactive as acceptors with the liver enzyme, inhibited to a small extent. Low levels of inhibition were also observed with intact or degraded ribosomal RNA. Deoxyribonucleic acid from several species was a potent inhibitor of glutamyl-tRNA formation, although it exhibited a mixed type of inhibition with respect to tRNA. An unknown RNA component was isolated from pH 5 fractions of beef liver and was found to be a potent, competitive inhibitor of glutamyl-tRNA formation. This RNA had a low molecular weight, but no amino acid acceptor activity. It was a much more effective inhibitor than either degraded ribosomal RNA or tRNA whose terminal adenosine moiety had been removed, suggesting that this RNA is distinct from either of these two species. Studies with periodate-oxidized tRNA and tRNA whose terminal adenosine had been removed indicated the involvement of this terminal nucleoside moiety in the interaction of glutamate-specific tRNA and its synthetase. The observation that several naturally occurring nucleic acids can inhibit aminoacyl-tRNA formation warns against the use of impure tRNA preparations in the study of aminoacyl-tRNA synthetases. The possible regulatory significance of the inhibition of aminoacyl-tRNA formation is discussed.

Inhibition of aminoacyl transfer ribonucleic acid synthetases by modified transfer ribonucleic acids.

Inhibition of aminoacyl transfer ribonucleic acid synthetases by modified transfer ribonucleic acids.

Amino Acid Esters as Inhibitors of Growth and of Aminoacyl Transfer Ribonucleic Acid Synthetases in Euglena and Astasia

Abstract At moderate concentrations the methyl, ethyl, or butyl esters of 10 amino acids inhibit the growth of Astasia. At least 8 of these also inhibit the growth of Euglena, although Euglena is generally less sensitive to these esters than Astasia. None of the amino acids tested at comparable concentrations inhibit growth except cysteine. The concentrations of ester required for 50% inhibition of growth rate depend not only on the amino acid, but on the ester group, increasing inhibition being generally observed with increasing size of the alcohol moiety. Recovery takes place primarily by nonenzymatic hydrolysis of the ester. Inhibition is highly pH-sensitive, with little inhibition below pH 5 and maximal inhibition above pH 6. Experiments with 14C-leucine ethyl ester indicate that Astasia is much less permeable to this ester at low pH. These observations led to the hypothesis that the amino acid esters inhibited growth by interfering with the corresponding aminoacyl transfer ribonucleic acid (tRNA) synthetases. Consistent with this hypothesis were the observations that: (a) phenylalanine ethyl ester inhibited the synthesis of an induced acid phosphatase; (b) the methyl and ethyl esters of serine, which did not inhibit growth, did not inhibit a partially purified seryl-tRNA synthetase of Astasia; (c) the methyl and ethyl esters of leucine, which inhibited growth, competitively inhibited the partially purified leucyl-tRNA synthetase of Astasia. Other growth experiments demonstrated that, whereas leucine slightly protected against growth inhibition by leucine ethyl ester, phenylalanine potentiated growth inhibition due to phenylalanine ethyl ester. It was then found that partially purified phenylalanyl-tRNA synthetase is inhibited by excess substrate concentrations. It is suggested that some amino acid esters may be useful inhibitors of the first committed steps of protein synthesis.

An assessment of polynucleotide inhibition studies of aminoacyl-transfer ribonucleic acid synthetases.

An assessment of polynucleotide inhibition studies of aminoacyl-transfer ribonucleic acid synthetases.

The effect of sodium chloride on esterification of leucine to transfer ribonucleic acid by heterologous aminoacyl transfer ribonucleic acid synthetases.

The effect of sodium chloride on esterification of leucine to transfer ribonucleic acid by heterologous aminoacyl transfer ribonucleic acid synthetases.