title: High temperature induction of a stringent response in the dnaK(Ts) and dnaJ(Ts) mutants of Escherichia coli.
abstract: The cellular concentrations of ppGpp in the dnaK(Ts) and dnaJ(Ts) mutants of Escherichia coli were examined, since the thermosensitive RNA synthesis of these mutants is relaxed by an additional mutation in the relA gene. The results showed that ppGpp accumulated extensively in the dnaK(Ts) and dnaJ(Ts) mutants after a temperature shift up, reaching levels of 5 mM and 0.5 mM, respectively. This unusual accumulation of ppGpp was suppressed by the relA1 mutation, implying that it results from induction of a stringent response in these mutants at a nonpermissive temperature.
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D001345:Autoradiography; D002855:Chromatography, Thin Layer; D004269:DNA, Bacterial / Q000096:biosynthesis; D004926:Escherichia coli / Q000235:genetics*; D005798:Genes, Bacterial; D006150:Guanine Nucleotides / Q000378:metabolism*; D006158:Guanosine Pentaphosphate / Q000378:metabolism; D006159:Guanosine Tetraphosphate / Q000235:genetics / Q000378:metabolism*; D006358:Hot Temperature; D009154:Mutation; D012329:RNA, Bacterial / Q000096:biosynthesis
chemical_list: D004269:DNA, Bacterial; D006150:Guanine Nucleotides; D012329:RNA, Bacterial; D006159:Guanosine Tetraphosphate; D006158:Guanosine Pentaphosphate; D000255:Adenosine Triphosphate