Seryl Transfer Ribonucleic Acid Research Articles

Protection of bovine seryl-transfer ribonucleic acid (seryl-tRNA) synthetase from chemical modification by its substrates, and some kinetic parameters.

Amino acid residues contained in the recognition sites of seryl-transfer ribonucleic acid (tRNA) synthetase (SerRS) were studied by chemical modification. Ser residues were modified with phenylmethanesulfonyl fluoride, and appeared to be unnecessary for the recognition. However, the modification of Arg residues with phenylglyoxal, His residues with diethylpyrocarbonate and sulfhydryl groups with 5, 5'-dithiobis (2-nitrobenzoic acid), N-ethylmaleimide, iodoacetic acid or iodoacetamide showed that these residues were essential for the tRNA recognition by SerRS. Protection experiments with substrates from inactivation of Ser-tRNA formation by modification suggested that Arg residues interact with the γ-phosphate of adenosine triphosphate and tRNA. Modification of sulfhydryl groups showed that the groups interact with the hydroxyl groups of ribose of the CCA-end on tRNA. Furthermore, in order to understand the recognition mechanism between SerRS and tRNAser, some kinetic parameters such as the Km and Vmax values of yeast tRNAser and E. coli tRNAser for bovine SerRS were compared with the values of bovine tRNAser.

Mutation in the structural gene for seryl-transfer ribonucleic acid synthetase of Escherichia coli which affects formation of its gene product at high temperature.

The rate of formation of seryl-transfer ribonucleic acid (tRNA) synthetase activity was temperature dependent in a temperature-sensitive mutant of Escherichia coli (K28) with an altered seryl-tRNA synthetase structural gene and in a class of spontaneous revertants derived from it. These revertants, which were selected by their ability to grow at 45 degrees C, had high levels of the thermolabile enzyme. The rate of formation of seryl-tRNA synthetase activity in the mutant and in the revertants fell from 100% to near zero with a 4 degrees C temperature range from 40 to 44 degrees C. The temperature-dependent rate of formation of seryl-tRNA synthetase activity was reversible. Dropping the temperature from 44 to 37 degrees C resulted, after a 2- to 3-min delay, in a resumption of the initial rate of formation of enzyme activity. The results could not be accounted for by in vivo or in vitro degradation of the active enzyme. Addition of rifampin just before the temperature shift down from 44 to 37 degrees C inhibited the appearance of seryl-tRNA synthetase activity at the lower temperature. Explanations which might account for these phenomena are proposed.

Transfer of serine into polypeptides and myosin by chromatographic species of seryl-transfer ribonucleic acid.

The efficiencies of two chromatographic species of [3-H]seryl-tRNA, namely peaks I and II, in cell-free amino acid incorporation were investigated. The maximum yield of polypeptide seems to be the same for the reaction mixtures containing either peak I or peak II, suggesting that the efficiency of both peaks in total protein synthesis is the same. The efficiency of transfer of serine into myosin heavy subunit (myosin H) by peaks I and II was also investigated. Peak II of [3-H]seryl-tRNA transfers three times as much serine into myosin H as peak I.

Purification of chicken liver seryl transfer ribonucleic acid by complex formation with elongation factor EF-Tu:GTP. A general micromethod of aminoacyl transfer ribonucleic acid purification.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTPurification of chicken liver seryl transfer ribonucleic acid by complex formation with elongation factor EF-Tu:GTP. General micromethod of aminoacyl transfer ribonucleic acid purificationBarry J. Klyde and Merton R. BernfieldCite this: Biochemistry 1973, 12, 19, 3752–3757Publication Date (Print):September 1, 1973Publication History Published online1 May 2002Published inissue 1 September 1973https://doi.org/10.1021/bi00743a026RIGHTS & PERMISSIONSArticle Views22Altmetric-Citations14LEARN 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 (648 KB) Get e-Alerts Get e-Alerts

Edman degradation on in vitro biosynthesized peptidoglycans from Staphylococcus epidermidis.

Edman degradations were performed on the pentapeptide bridges of peptidoglycans which were biosynthesized in vitro by using six different species of seryl-transfer ribonucleic acid (tRNA). The ratio of glycine to serine in each of the five bridge positions varied with the concentration of crude glycyl-tRNA contained in the reaction mixtures, and serine appeared to be incorporated in a random manner. No single species of seryl-tRNA could be identified as the one active in in vivo pentapeptide bridge synthesis; however, it can be speculated that seryl-tRNA(s) from category I could be involved in the in vivo nonrandom incorporation of serine in the bridge.

Seryl transfer ribonucleic acid synthetase of Escherichia coli B, Enzyme-substrate interactions.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSeryl transfer ribonucleic acid synthetase of Escherichia coli B. Enzyme-substrate interactionsElizabeth A. Boeker and Giulio L. CantoniCite this: Biochemistry 1973, 12, 13, 2384–2389Publication Date (Print):June 1, 1973Publication History Published online1 May 2002Published inissue 1 June 1973https://doi.org/10.1021/bi00737a003RIGHTS & PERMISSIONSArticle Views24Altmetric-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 (648 KB) Get e-Alerts Get e-Alerts

Seryl transfer ribonucleic acid synthetase of Escherichia coli B. Purification, subunit structure, and behavior in the acylation reaction

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSeryl transfer ribonucleic acid synthetase of Escherichia coli B. Purification, subunit structure, and behavior in the acylation reactionElizabeth A. Boeker, Arthur P. Hays, and Giulio L. CantoniCite this: Biochemistry 1973, 12, 13, 2379–2383Publication Date (Print):June 1, 1973Publication History Published online1 May 2002Published inissue 1 June 1973https://doi.org/10.1021/bi00737a002RIGHTS & PERMISSIONSArticle Views22Altmetric-Citations15LEARN 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 (1 MB) Get e-Alerts Get e-Alerts

Effect of Serine Hydroxamate on Phospholipid Synthesis in Escherichia coli

Serine hydroxamate, which inhibits the charging of seryl-transfer ribonucleic acid, reduced the synthesis of phospholipid and nucleic acids in Escherichia coli. This effect was analogous to depriving amino acid auxotrophs of their nutritional requirement and appears to be a manifestation of the stringent response shown by rel(+) strains of E. coli. Amino acid starvation (serine or methionine) alone or serine hydroxamate treatment alone results in 60 to 80% inhibition of lipid accumulation, 90% inhibition of ribonucleic acid accumulation, and an increase in guanosine tetraphosphate (ppGpp). These three effects were reversed by addition of chloramphenicol (CM). A combination of serine starvation and serine hydroxamate treatment resulted in inhibition of lipid and RNA accumulation as well as an increase in ppGpp, but the consequences of the double block were not reversed by CM. We conclude that a strong interrelationship exists among these processes and that CM acts to relax a stringent response by mechanisms other than interference with ppGpp formation. All species of phospholipid were affected by a stringent response evoked by amino acid starvation or addition of serine hydroxamate, but in all cases the synthesis of phosphatidylethanolamine was most severely inhibited. Serine hydroxamate was not incorporated into lipid but specifically caused phosphatidylserine accumulation. Serine starvation produced a dramatic alteration of the distribution of isotope incorporated into phospholipid, which resulted from the stringent response compounded with the limitation of a substrate for phosphatidylserine synthesis.

Isolation and characterization of a regulatory mutant of an aminoacyl-transfer ribonucleic acid synthetase in Escherichia coli K-12.

From Escherichia coli strain K28, which is temperature sensitive for growth because of a mutation in its seryl-transfer ribonucleic acid (tRNA) synthetase gene (serS), temperature-resistant mutants were selected which were found to have a fivefold higher level of seryl-tRNA synthetase than the parent strain. The "high-level" character was found to be genetically stable and is due to a mutation in a locus denoted serO. This locus was found to be very closely linked to serS on the genetic map, and the relative gene order was concluded to be serS-serO-serC. In a serO(-) strain, the normal dependence of seryl-tRNA synthetase (SerRS) activity on changes of exogenous serine concentration was not observed. In a stable heterozygous merodiploid, the serO(-) mutation is still expressed, i.e., it is cis dominant. These results strongly suggest that serO is an operator site involved in the control of the serS gene.

Close linkage of the genes serC (for phosphohydroxy pyruvate transaminase) and serS (for seryl-transfer ribonucleic acid synthetase) in Escherichia coli K-12.

Escherichia coli strain K28, isolated after nitrosoguanidine mutagenesis, was found to be auxotrophic for serine. It was also temperature sensitive for growth as a result of producing an altered seryl-transfer ribonucleic acid (tRNA) synthetase (EC 6.1.1.11, l-serine: tRNA ligase [AMP]). The auxotrophy was caused by a mutation in the structural gene for phosphohydroxy-pyruvate transaminase (serC), which was distinct from, but closely linked to, the structural gene for seryl-tRNA synthetase (serS). We conclude that the relevant genes are in the order gal-serS-serC-aroA.

Isolation and partial characterization of temperature-sensitive Escherichia coli mutants with altered leucyl- and seryl-transfer ribonucleic acid synthetases.

Two temperature-sensitive mutants of Escherichia coli have been found in which the conditional growth is a result of a thermosensitive leucyl-transfer ribonucleic acid (tRNA) synthetase and seryl-tRNA synthetase, respectively. The corresponding genetic loci, leuS and serS, cotransduce with lip and serC, respectively. As a result of the mutationally altered leucyl-tRNA synthetase, some leucine-, valine-, and isoleucine-forming enzymes were derepressed. Thus, leucyl-tRNA synthetase is involved in the repression of the enzymes needed for the synthesis of branched-chain amino acids.

Biochemical bases for the antimetabolite action of L-serine hydroxamate.

The amino acid analogue l-serine hydroxamate, which is bacteriostatic for Escherichia coli, has been shown to inhibit protein synthesis. The antimetabolite is a competitive inhibitor of seryl-transfer ribonucleic acid (tRNA) synthetase with a K(i) value of 30 mum. Mutants resistant to l-serine hydroxamate have been selected, and three were shown to have seryl-tRNA synthetases with increased K(i) values. One mutant contains a 3-phosphoglycerate dehydrogenase which is insensitive to inhibition by l-serine.

The Interaction of Seryl and of Leucyl Transfer Ribonucleic Acid Synthetases with Their Cognate Transfer Ribonucleic Acids

SUMMARY Density gradient centrifugation and gel filtration have been used to study the formation and some properties of stable complexes between seryl transfer ribonucleic acid synthetase and leucyl transfer ribonucleic acid synthetase and their cognate transfer RNA species (contained in unfractionated tRNA) from Escherichia coli. The molar ratio of tRNA to enzyme was measured as 0.8: 1 for tRNASer and seryl-tRNA synthetase. The complex formation is specific with the cognate tRNA. Five purified different isoaccepting E. coli tRNASe’ species have been shown to form complexes with the enzyme. The presence of high salt (0.5

Purification of Five Serine Transfer Ribonucleic Acid Species from Escherichia coli and Their Acylation by Homologous and Heterologous Seryl Transfer Ribonucleic Acid Synthetases

can esterify serine to all of the purified isoacceptor RNAs. However, the extent of charging is only a small fraction of the level obtained with the homologous seryl-tRNA synthetase. It has been well established that most amino acids are speci- fied by more than one codon. A single tRNA molecule, how- ever, can recognize only one, two, or three codons. Thus, the proper translation of the genetic message to an amino acid specified by four codons, for example, requires at least two tRNA species (1, 2). This explains the occurrence in cells of families of tRNAs with different coding response but specifying the same amino acid (isoaccepting tRNAs). The number of such isoacceptors is further increased by the existence of multiple tRNA species specific for the same ammo acid and the same codon (redundant tRNAs (2)). Since leucine, serine, and arginine each have six codons, a larger number of isoacceptor RNAs is expected for these amino acids than for all others. Of these, the family of serine tRNAs has been most carefully studied, and there are three reports (3-5) of separation and partial puri- fication of the tRNASer family from Escherichia coli. This report describes a more extensive separation and purifi- * This work was supported by Grants GM 15401 and FR-07015 from the United States Public Health Service, National Institutes of Health, and Grant GB 7269 from the National Science Foun- dation. $ Centennial Fellow

Purification and Properties of Seryl Transfer Ribonucleic Acid Synthetase from Escherichia coli

Abstract Seryl-tRNA synthetase (EC 6.1.1.11, l-serine:tRNA ligase (AMP)) has been purified to apparent homogeneity from Escherichia coli K12. The protein has a molecular weight of 95,000 to 100,000 and appears to be a dimer of identical subunits. It is suggested that there is a single seryl-tRNA synthetase in E. coli.