title: Formylmethionyl-tRNA alters RNA polymerase specificity.
abstract: Escherichia coli fMet-tRNAfMet alters the pattern of promoter selection of E. coli RNA polymerase (RNA nucleotidyltransferase, nucleosidetriphosphate:RNA nucleotidyltransferase; EC 2.7.7.6), affecting RNA synthesis from the rRNA, suIII+tRNA, and lac promoters in different ways. The in vitro synthesis of the stable RNA species is selectively decreased, whereas that of lac RNA from both the wild-type and mutant UV5 promoters is selectively increased at high ionic strength. The functional effect of fMet-tRNAfMet resembles that of the nucleotide guanosine 3'-diphosphate 5'-diphosphate (ppGpp). This nucleotide competes with the binding of fMet-tRnafMet to RNA polymerase.
mesh_terms: D001667:Binding, Competitive; D004269:DNA, Bacterial / Q000378:metabolism; D012321:DNA-Directed RNA Polymerases / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics*; D006159:Guanosine Tetraphosphate / Q000378:metabolism; D009239:N-Formylmethionine; D009876:Operon; D012346:RNA, Transfer, Amino Acyl / Q000378:metabolism / Q000494:pharmacology*; D013379:Substrate Specificity; D013698:Templates, Genetic; D014158:Transcription, Genetic
chemical_list: D004269:DNA, Bacterial; D012346:RNA, Transfer, Amino Acyl; D006159:Guanosine Tetraphosphate; D009239:N-Formylmethionine; D012321:DNA-Directed RNA Polymerases