title: Mutation affecting thermostability of sigma subunit of Escherichia coli RNA polymerase lies near the dnaG locus at about 66 min on the E. coli genetic map.
abstract: The Escherichia coli strain, ts-rnp5, originally described in 1975 by G. D. Burdick and H. Berger, is shown to possess an RNA polymerase (RNA nucleotidyltransferase) sigma subunit with an activity 4--6 times less thermostable at 45 degrees than sigma from wild-type strains. This defect remains associated with the sigma polypeptide through a variety of purification stages, including renaturation of sigma after its elution from sodium dodecyl sulfate/polyacrylamide gels. The mutation responsible for decreased thermostability of sigma, called rpoD1, cotransduces with dnaG and therefore is located at about 66 min of the E. coli genetic map.
mesh_terms: D002874:Chromosome Mapping; D012321:DNA-Directed RNA Polymerases / Q000235:genetics*; D004926:Escherichia coli / Q000235:genetics*; D005796:Genes; D008040:Genetic Linkage; D009154:Mutation; D012808:Sigma Factor / Q000235:genetics*; D013696:Temperature; D014157:Transcription Factors / Q000235:genetics*; D014161:Transduction, Genetic
chemical_list: D012808:Sigma Factor; D014157:Transcription Factors; D012321:DNA-Directed RNA Polymerases