This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Hennecke, H.
Right arrow Articles by Nass, G.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Hennecke, H.
Right arrow Articles by Nass, G.

 Previous Article  |  Next Article 

J Bacteriol. 1977 September; 131(3): 943-950
Copyright © 1977 American Society for Microbiology. All Rights Reserved.

Threonyl-Transfer Ribonucleic Acid Synthetase from Escherichia coli: Subunit Structure and Genetic Analysis of the Structural Gene by Means of a Mutated Enzyme and of a Specialized Transducing Lambda Bacteriophage

H. Hennecke1, A. Böck1, J. Thomale1 and G. Nass*

Lehrstuhl für Mikrobiologie der Universität Regensburg, D-8400 Regensburg, Federal Republic of Germany
* Max-Planck-Institut für Experimentelle Medizin, Abteilung Molekulare Biologie, D-3400 Göttingen, Federal Republic of Germany

ABSTRACT

Threonyl-transfer ribonucleic acid synthetase (ThrRS) has been purified from a strain of Escherichia coli that shows a ninefold overproduction of this enzyme. Determination of the molecular weight of the purified, native enzyme by gel chromatography and by polyacrylamide gel electrophoresis at different gel concentrations yielded apparent molecular weight values of 150,000 and 161,000, respectively. Polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate yields a single protein band of 76,000-dalton size. From these results an {alpha}2 subunit structure can be inferred. A mutant with a structurally altered ThrRS, which had been obtained by selection for resistance against the antibiotic borrelidin, was used to map the position of the ThrRS structural gene (thrS) by P1 transductions. It was found that thrS is located in the immediate neighborhood of pheS and pheT, which are the structural genes for the {alpha} and ß subunits of phenylalanyl-transfer ribonucleic acid (tRNA) synthetase, the gene order being aroD-pheT-pheS-thrS. A {lambda} phage that was previously shown to specifically transduce pheS, pheT, and also the structural gene for the translation initiation factor IF3 can complement the defect of the altered ThrRS of the borrelidin-resistant strain. This phage also stimulates the synthesis of the 76,000, molecular-weight polypeptide of ThrRS in ultraviolet light-irradiated. E. coli cells. These results indicate that the genes for ThrRS, {alpha} and ß subunits of phenylalanyl-tRNA synthetase, and initiation factor IF3 are immediately adjacent on the E. coli chromosome.

J Bacteriol. 1977 September; 131(3): 943-950
Copyright © 1977 American Society for Microbiology. All Rights Reserved.





Copyright © 2009 by the American Society for Microbiology.   For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»