title: Intracellular inducer Hg2+ concentration is rate determining for the expression of the mercury-resistance operon in cells.
abstract: Experiments involving mercury resistance mer operon-lacZ fusions, point mutations in the mercuric ion reductase merA gene, and transcomplementation have revealed that in Hg2+-resistant cells, the inducer Hg2+ concentration is rate determining for activation of transcription. mer operon expression is activated by the presence of nanomolar concentrations of Hg2+ in liquid media only when the mercuric ion reductase function is artificially inactivated in cells, whereas cells with active mercuric ion reductase require micromolar concentrations of Hg2+ for effective induction of the operon.
authors.affiliation: Department of Microbiology and Immunology, University of Illinois College of Medicine, Chicago, 60612-7344, USA.
authors.forename: H
authors.initials: H
authors.lastname: Yu
authors.forename: L
authors.initials: L
authors.lastname: Chu
authors.forename: T K
authors.initials: TK
authors.lastname: Misra
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics; D004352:Drug Resistance, Microbial; D004790:Enzyme Induction / Q000187:drug effects; D004926:Escherichia coli / Q000187:drug effects* / Q000235:genetics; D015964:Gene Expression Regulation, Bacterial / Q000187:drug effects*; D017136:Ion Transport; D008190:Lyases; D008627:Mercuric Chloride / Q000494:pharmacology*; D008628:Mercury / Q000032:analysis / Q000378:metabolism; D009876:Operon; D010088:Oxidoreductases / Q000096:biosynthesis / Q000235:genetics*; D017354:Point Mutation; D011993:Recombinant Fusion Proteins; D001616:beta-Galactosidase / Q000235:genetics
chemical_list: D001426:Bacterial Proteins; D011993:Recombinant Fusion Proteins; D008627:Mercuric Chloride; D010088:Oxidoreductases; C021551:mercuric reductase; D001616:beta-Galactosidase; D008190:Lyases; C097247:MerB protein, Bacteria; D008628:Mercury