Cooperative control of translational fidelity by ribosomal proteins in Escherichia coli
- 37 Downloads
Two spontaneous mutants of Escherichia coli strain KMBL-146 selected for resistance to the aminoglycoside antibiotic neamine show severe restriction of amber suppressors in vivo. Purified ribosomes from the mutant strains exhibit low neamine-induced misreading in vitro and a decreased affinity for the related antibiotic streptomycin.
Biochemical analysis shows that the mutants each have two modified 30S ribosomal proteins, S12 and S5. In agreement with these results, genetic analysis shows that two mutations are present, neither of which confers resistance to neamine by itself; the mutation located in gene rpxL (the structural gene for protein S12) confers streptomycin dependence but this dependence is suppressed in the presence of the second mutation, located in gene rpxE (the structural gene for protein S5).
KeywordsEscherichia Coli Genetic Analysis Streptomycin Structural Gene Mutant Strain
Unable to display preview. Download preview PDF.
- Davies, J.: Structure-activity relationships among amino-glycosides antibiotics. Antimicrobial agents and chemotherapy 297–303 (1967)Google Scholar
- Gordon, J., Lucas-Lenard, D. L., Lipmann, F.: Isolation of bacterial chain elongation factors in “Methods in Enzymology” 20, 821 (1971)Google Scholar
- Jaskunas, S. R., Nomura, M., Davies, J.: Genetics of bacterial ribosomes. In “Ribosomes” p. 333–368. Cold Spring: Harb. Laboratory Ed. 1974Google Scholar
- Miller, J. H.: Experiments in molecular genetics, p. 221–229. Cold Spring: Harb. Laboratory Ed. 1972Google Scholar
- Ravel, J., Shorey, R. A. L.: GTP-dependent binding of aminoacyl-tRNA, to Escherichia coli ribosomes. In “Methods in Enzymology” 20, 306–316 (1971)Google Scholar
- Traub, P., Mizushima, S., Lowry, C. V., Nomura, M.: Reconstitution of ribosomes from subribosomal components. In “Methods in Enzymology” 20, 391–407 (1971)Google Scholar
- Wittmann, H. G., Stöffler, G., Hindenach, I., Kurland, C. B., Randall-Hazelbauer, L., Birge, E. A., Nomura, M., Kaltschmidt, E., Mizushima, S., Traut, R. R., Bickle, T. A.: Correlation of 30S ribosomal proteins of Escherichia coli isolated in different laboratories. Molec. gen. Genet. 111, 327–333 (1971)CrossRefGoogle Scholar
- Wittmann, H. G., Stöffler, R. G., Apirion, D., Rosen, L., Tanaka, K., Tamaki, M., Takata, R., Dekio, S., Otaka, E., Osawa, S.: Biochemical and genetic studies on two different types of erythromycin resistant mutants of Escherichia coli with altered ribosomal proteins. Molec. gen. Genet. 127, 175–189 (1973)CrossRefGoogle Scholar