title: Glutamine synthetase gene expression at elevated hydrostatic pressure in a deep-sea piezophilic Shewanella violacea.
abstract: A glutamine synthetase gene (glnA) was isolated from a deep-sea piezophilic bacterium, Shewanella violacea strain DSS12. A 7.5-kb SacI fragment containing the complete glnA gene was cloned and sequenced. The glnA gene was found to encode a protein consisting of 469 amino acid residues, showing 75.0% identity to the glutamine synthetase of Escherichia coli. Primer extension analyses revealed two transcription initiation sites in glnA and expression from each site was positively regulated by pressure. Putative promoters recognized by sigma(70) and sigma(54) were identified in the region upstream of glnA. An electrophoretic mobility shift assay demonstrated that S. violacea sigma(54) specifically binds to the promoter region of glnA, suggesting that sigma(54) may play an important role in pressure-regulated transcription in this piezophilic bacterium.
authors.affiliation: The DEEPSTAR Group, Japan Marine Science and Technology Center, Yokosuka, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Ikegami
authors.forename: K
authors.initials: K
authors.lastname: Nakasone
authors.forename: C
authors.initials: C
authors.lastname: Kato
authors.forename: Y
authors.initials: Y
authors.lastname: Nakamura
authors.forename: I
authors.initials: I
authors.lastname: Yoshikawa
authors.forename: R
authors.initials: R
authors.lastname: Usami
authors.forename: K
authors.initials: K
authors.lastname: Horikoshi
mesh_terms: D001483:Base Sequence; D003001:Cloning, Molecular; D004268:DNA-Binding Proteins; D012321:DNA-Directed RNA Polymerases / Q000378:metabolism; D029968:Escherichia coli Proteins; D015964:Gene Expression Regulation, Bacterial; D005974:Glutamate-Ammonia Ligase / Q000235:genetics* / Q000378:metabolism; D006874:Hydrostatic Pressure; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic / Q000235:genetics; D051877:RNA Polymerase Sigma 54; D012623:Seawater / Q000382:microbiology*; D017422:Sequence Analysis, DNA; D020592:Shewanella / Q000201:enzymology* / Q000235:genetics*; D012808:Sigma Factor / Q000378:metabolism; D014158:Transcription, Genetic / Q000235:genetics
chemical_list: D004268:DNA-Binding Proteins; D029968:Escherichia coli Proteins; D012808:Sigma Factor; C497751:rpoN protein, E coli; D012321:DNA-Directed RNA Polymerases; D051877:RNA Polymerase Sigma 54; D005974:Glutamate-Ammonia Ligase