Transcriptional regulation of the Na(+)-NADH: Quinone oxidoreductase gene, nqr, in Vibrio anguillarum, a fish pathogen, in the stationary phase

• Published in: Fisheries science Vol. 73; no. 2; pp. 348 - 355
• Main Authors: Fujiwara Nagata, E.(Kinki Univ., Nara (Japan)), Eguchi, Y, Utsumi, R, Eguchi, M
• Format: Journal Article
• Language: English
• Published: Melbourne, Australia Blackwell Publishing Asia 01.04.2007; Springer Nature B.V
• Subjects: AGENT PATHOGENE; Amino acids; Aquaculture; Bacteria; Bacteriology; Cloning; COENZIMAS; COENZYME; COENZYMES; E coli; fish pathogen; FISHES; GENE; GENES; Na+‐NADH:quinone oxidoreductase; ORGANISMOS PATOGENOS; OXIDOREDUCTASES; OXIDORREDUCTASAS; OXYDOREDUCTASE; PATHOGENS; PECES; POISSON (ANIMAL); QUINONAS; QUINONE; QUINONES; Seawater; starvation‐survival; TRANSCRIPCION; TRANSCRIPTION; VIBRIO ANGUILLARUM
• ISSN: 0919-9268; 1444-2906
• DOI: 10.1111/j.1444-2906.2007.01341.x

Vibrio anguillarum kills various kinds of fish over a range of salinities from sea water to fresh water, and causes serious damage to aquaculture systems. In this study, the transcriptional regulation of the Na+‐NADH:quinone oxidoreductase (Na+‐NQR) operon in V. anguillarum from the logarithmic to stationary phases was investigated. Cloning of the Na+‐NQR operon revealed a 7 kb nucleotide sequence composed of six open reading frames with amino acid sequence identity of more than 80% with other Vibrio species. Two promoters, nqrP1 and nqrP2, were identified in the region upstream of the nqrA gene using an S1 nuclease assay. The nqrP1 promoter was constitutively activated throughout the logarithmic to stationary phases and possessed ‐10 (5′‐TAGACT‐3′) and ‐35 (5′‐ATGGCA‐3′) sequences, which were similar to the consensus sequence of Escherichia coli. On the other hand, the nqrP2 promoter was activated only at the stationary phase and had only a ‐10 (5′‐CATACT‐3′) and not a ‐35 sequence. These results suggest that nqrP2, which works specifically in the stationary phase, contributes to starvation‐survival in V. anguillarum.