Polyamine limitation of growth slows the rate of polypeptide chain elongation in Escherichia coli.
The rate of polypeptide chain elongation during steady-state, polyamine-limited growth of a mutant of Escherichia coli was measured by two independent techniques. Analysis of polysome patterns gave values of 17.5 and 9.5 amino acids per s at 37 C in unstarved and polyamine-limited cells, respectively. From the kinetics of entry of labeled amino acids into polypeptides of defined molecular weights, values at 30 C of 10.1 and 5.8 amino acids per s were obtained for unstarved and polyamine-limited cultures, respectively. Correction of these values to 37 C resulted in rates of 15.0 and 8.7 amino acids per s. These results support the previous conclusion, based on the kinetics of beta-galactosidase induction, that polyamine starvation decreases the rate of protein synthesis by limiting the velocity of polypeptide chain elongation.
D001426:Bacterial Proteins / Q000096:biosynthesis; D002250:Carbon Radioisotopes; D004926:Escherichia coli / Q000254:growth & development / Q000378:metabolism*; D009154:Mutation; D010452:Peptide Biosynthesis; D010441:Peptide Chain Elongation, Translational; D010649:Phenylalanine / Q000378:metabolism; D011132:Polyribosomes / Q000378:metabolism; D011700:Putrescine / Q000378:metabolism*; D014498:Uracil / Q000378:metabolism
D001426:Bacterial Proteins; D002250:Carbon Radioisotopes; D010649:Phenylalanine; D014498:Uracil; D011700:Putrescine