title: Overexpression of MerT, the mercuric ion transport protein of transposon Tn501, and genetic selection of mercury hypersensitivity mutations.
abstract: The small (116 amino acids) inner membrane protein MerT encoded by the transposon Tn501 has been overexpressed under the control of the bacteriophage T7 expression system. Random mutants of MerT were made and screened for loss of mercuric ion hypersensitivity. Several mutant merT genes were selected and sequenced: Cys24Arg and Cys25Tyr mutations abolish mercury resistance, as do charge-substitution mutations in the first predicted transmembrane helix (Gly14Arg, Gly15Arg, Gly27Arg, Ala18Asp), and the termination mutations Trp66Ter and Cys82Ter.
authors.affiliation: School of Biological Sciences, University of Birmingham, Edgbaston, UK.
authors.forename: J L
authors.initials: JL
authors.lastname: Hobman
authors.forename: N L
authors.initials: NL
authors.lastname: Brown
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D001483:Base Sequence; D002352:Carrier Proteins / Q000235:genetics* / Q000378:metabolism; D027682:Cation Transport Proteins; D004251:DNA Transposable Elements; D004269:DNA, Bacterial; D004926:Escherichia coli / Q000235:genetics; D015964:Gene Expression Regulation, Bacterial; D008565:Membrane Proteins / Q000235:genetics* / Q000378:metabolism; D008628:Mercury / Q000494:pharmacology*; D008969:Molecular Sequence Data; D009154:Mutation; D011506:Proteins
chemical_list: D001426:Bacterial Proteins; D002352:Carrier Proteins; D027682:Cation Transport Proteins; D004251:DNA Transposable Elements; D004269:DNA, Bacterial; D008565:Membrane Proteins; C086060:MerP protein, Bacteria; D011506:Proteins; C094115:mercury transport protein, bacterial; D008628:Mercury