Open AccessGlutamine synthetase gene expression at elevated hydrostatic pressure in a deep‐sea piezophilic Shewanella violacea
Author(s) -
Ikegami Akihiko,
Nakasone Kaoru,
Kato Chiaki,
Nakamura Yuka,
Yoshikawa Ikuko,
Usami Ron,
Horikoshi Koki
Publication year - 2000
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.2000.tb09364.x
Subject(s) - glutamine synthetase , biology , gene , transcription (linguistics) , microbiology and biotechnology , promoter , hydrostatic pressure , sigma factor , gene expression , genetics , glutamine , amino acid , linguistics , philosophy , thermodynamics , physics
A glutamine synthetase gene ( glnA ) was isolated from a deep‐sea piezophilic bacterium, Shewanella violacea strain DSS12. A 7.5‐kb Sac I 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 σ 70 and σ 54 were identified in the region upstream of glnA . An electrophoretic mobility shift assay demonstrated that S. violacea σ 54 specifically binds to the promoter region of glnA , suggesting that σ 54 may play an important role in pressure‐regulated transcription in this piezophilic bacterium.