title: Polypeptide-chain-elongation rate in Escherichia coli B/r as a function of growth rate.
abstract: By evaluating the kinetics of radioactive labelling of nascent and finished polypeptides, the peptide-chain elongation rate for Escherichia coli B/r at three different growth rates (mu) was determined to be 17 amino acids/s for the fast-growing cells (mu equals 1.3 and 2.0 doublings/h) and 12 amino acids/s for slow-growing cells (mu equals 0.67 doublings/h). The results agree with the growth-rate-dependence of the rate of peptide-chain elongation found for the translation of newly induced beta-galactosidase messenger in this strain and under these conditions of growth [Dalbow & Young (1975) Biochem. J. 150, 13-20]. Together with the previously observed ribosome efficiency at these growth rates [Dennis & Bremer (1974) J. Mol. Biol. 84, 407-422] the results indicate that the fraction of ribosomes engaged in protein synthesis is about 0.8 at all three growth rates.
mesh_terms: D001426:Bacterial Proteins / Q000096:biosynthesis; D004790:Enzyme Induction; D004926:Escherichia coli / Q000254:growth & development / Q000378:metabolism*; D005696:Galactosidases / Q000096:biosynthesis; D007700:Kinetics; D008954:Models, Biological; D008970:Molecular Weight; D010441:Peptide Chain Elongation, Translational; D012270:Ribosomes / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D005696:Galactosidases