Piezoregulation of cytochrome bd biosynthesis in deep-sea bacterium Shewanella violacea DSS 12
The genes of cytochrome bd-encoding cydAB were identified from a deep-sea bacterium Shewanella violacea DSS12. The sequences of them showed significant homologies to those of known cydAB from various organisms. In addition, highly conserved regions that are important for the enzymatic function were also conserved in cydA of S. violacea. It showed that cydAB may be functional in the cells of S. violacea. Based on the results, transcriptional analysis of cydAB operon and cydDC operon of S. violacea in microaerobic condition was performed under the growth condition of various pressures. The gene of cydA was expressed even under the condition of atmospheric pressure and the expression of it was enhanced with pressurization. On the other hand, the expression of cydC was strongly depressed under the condition of atmospheric pressure compared with the case under high pressure. It appeared that spectrophotometrically loss of cytochrome bd in S. violacea under atmospheric pressure showed in previous study is caused mainly by the loss of cydDC. These results suggested that the significant amount of d-type cytochrome expression is specific event under the growth condition of high pressure.
近畿大学工学部研究報告 39, 11-14, 2005-12-20