title: Effect of mutations in dnaK and dnaJ genes on cysteine operon expression in Escherichia coli.
abstract: The effect of mutations in dnaK and dnaJ genes on the expression of two operons that are part of cysteine regulon was determined using Escherichia coli strains harboring cysPTWA::lacZ and cysJIH::lacZ fusions. Null dnaJ and dnaKdnaJ mutants were impaired in beta-galactosidase expression from both fusions. Efficient complementation of this defect by wild-type alleles present on a low-copy number plasmid was achieved. The presence of the pMH224 plasmid coding for CysB* protein defective in DNA binding lowered beta-galactosidase expression from cysPTWA::lacZ fusion strain harboring wild-type dnaKdnaJ alleles but did not diminish enzyme expression in delta dnaJ and delta dnaKdnaJ strains.
authors.affiliation: Department of Bacterial Genetics, Institute of Microbiology, Warsaw University, 02-096 Warsaw, Poland.
authors.forename: P
authors.initials: P
authors.lastname: Karpiński
authors.forename: A
authors.initials: A
authors.lastname: Grudniak
authors.forename: K I
authors.initials: KI
authors.lastname: Wolska
mesh_terms: D000483:Alleles; D019677:Artificial Gene Fusion; D003545:Cysteine / Q000235:genetics; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics*; D029968:Escherichia coli Proteins; D015870:Gene Expression; D005798:Genes, Bacterial; D005816:Genetic Complementation Test; D050956:HSP40 Heat-Shock Proteins; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics*; D006360:Heat-Shock Proteins / Q000235:genetics*; D007763:Lac Operon; D009154:Mutation; D009876:Operon; D010957:Plasmids / Q000235:genetics; D001616:beta-Galactosidase / Q000235:genetics
chemical_list: C494635:DnaJ protein, E coli; D029968:Escherichia coli Proteins; D050956:HSP40 Heat-Shock Proteins; D018840:HSP70 Heat-Shock Proteins; D006360:Heat-Shock Proteins; D001616:beta-Galactosidase; C063842:dnaK protein, E coli; D003545:Cysteine