title: Characterization of the Escherichia coli K12 gltS glutamate permease gene.
abstract: The gltS gene is known to encode a sodium-dependent, glutamate-specific permease. We have localized the Escherichia coli K12 gltS gene with respect to the spoT gene, sequenced it, and recombined a null insertion-deletion allele into the chromosome without loss of viability. The gltS null allele gives a Glt- phenotype, i.e. it abolishes the ability of a gltCc host to grow on glutamate as sole carbon and nitrogen source and also confers alpha-methylglutamate resistance. A multicopy plasmid expressing the gltS gene can reverse the Glt- phenotype of gltS- or wild-type strains while other plasmids show host-dependent complementation patterns. Induction of gltS gene overexpression under control of isopropyl-beta-D-thiogalactoside (IPTG)-inducible promoters severely inhibits growth. The GltS protein is deduced to be a 42425 dalton hydrophobic protein with 2 sets of 5 possible integral protein domains, each flanking a central hydrophilic, flexible region.
authors.affiliation: Laboratory of Molecular Genetics, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892.
authors.forename: M
authors.initials: M
authors.lastname: Kalman
authors.forename: D R
authors.initials: DR
authors.lastname: Gentry
authors.forename: M
authors.initials: M
authors.lastname: Cashel
mesh_terms: D000483:Alleles; D000595:Amino Acid Sequence; D026922:Amino Acid Transport Systems, Acidic; D001483:Base Sequence; D004269:DNA, Bacterial; D004926:Escherichia coli / Q000187:drug effects / Q000201:enzymology / Q000235:genetics* / Q000254:growth & development; D029968:Escherichia coli Proteins; D016368:Frameshift Mutation; D005798:Genes, Bacterial; D005816:Genetic Complementation Test; D008040:Genetic Linkage; D005971:Glutamates / Q000378:metabolism / Q000494:pharmacology; D007544:Isopropyl Thiogalactoside / Q000235:genetics; D026901:Membrane Transport Proteins / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D010641:Phenotype; D010957:Plasmids; D016133:Polymerase Chain Reaction; D011401:Promoter Regions, Genetic; D015183:Restriction Mapping; D027981:Symporters
chemical_list: D026922:Amino Acid Transport Systems, Acidic; D004269:DNA, Bacterial; D029968:Escherichia coli Proteins; D005971:Glutamates; D026901:Membrane Transport Proteins; D027981:Symporters; C066603:gltS protein, E coli; D007544:Isopropyl Thiogalactoside; C025648:2-methylglutamic acid