title: Escherichia coli K-12 lysyl-tRNA synthetase mutant with a novel reversion pattern.
abstract: Fast-growing revertants have been selected from a slow-growing lysyl-tRNA synthetase mutant. All of the revertants had increased lysyl-tRNA synthetase activity compared with the mutant (5- to 85-fold), and in some revertants this amounted to two to three times the wild-type synthetase activity. Two-dimensional gel electrophoresis of a whole-cell extract of revertant IH2018 (1.5- to 2-fold wild-type synthetase activity) showed that the increase in synthetase activity is due to the induction of cryptic lysyl-tRNA synthetase forms and not to a change in the constitutive lysyl-tRNA synthetase. Genetic studies have shown that a locus termed rlu (for regulation of lysU ) which is cotransducible with purF at 49.5 min influences the amount of the cryptic lysyl-tRNA synthetase.
mesh_terms: D000604:Amino Acyl-tRNA Synthetases / Q000235:genetics*; D003227:Conjugation, Genetic; D004926:Escherichia coli / Q000201:enzymology* / Q000235:genetics; D005798:Genes, Bacterial; D005809:Genes, Regulator; D008250:Lysine-tRNA Ligase / Q000096:biosynthesis / Q000235:genetics*; D009154:Mutation; D013696:Temperature; D014161:Transduction, Genetic
chemical_list: D000604:Amino Acyl-tRNA Synthetases; D008250:Lysine-tRNA Ligase