Translational frameshifts induced by mutant species of the polypeptide chain elongation factor Tu of Escherichia coli.
Translational frameshifts, both +1 and -1, are promoted by mutations in tufA and tufB, the two genes encoding the polypeptide chain elongation factor (EF) Tu of Escherichia coli. Strains harboring the mutant EF-Tu(Ala375----Thr) encoded by either tufA or tufB or by both, display a linear relationship between the frequency of frameshifting and the concentration of mutant EF-Tu, relative to the total amount of EF-Tu. A second mutant species, EF-TuB(Gly222----Asp), also promotes frameshifting. The frequency is strikingly enhanced by the combined action of EF-TuA(Ala375----Thr) and EF-TuB(Gly222----Asp) and exceeds by far the total contribution of the two mutant EF-Tus studied separately. These observations raise the question whether the formation of each peptide bond under conditions that no frameshifting occurs also requires the combined action of two EF-Tu molecules, in this case not differing functionally.
Vijgenboom
E
E
Department of Biochemistry, Leiden University, The Netherlands.
Bosch
L
L
D001426:Bacterial Proteins / Q000235:genetics / Q000502:physiology; D001483:Base Sequence; D003001:Cloning, Molecular; D004926:Escherichia coli / Q000235:genetics*; D005798:Genes, Bacterial; D008969:Molecular Sequence Data; D009154:Mutation; D010444:Peptide Elongation Factor Tu / Q000235:genetics* / Q000502:physiology; D014176:Protein Biosynthesis; D013489:Suppression, Genetic
D001426:Bacterial Proteins; D010444:Peptide Elongation Factor Tu