Kato, C; Sato, T; Abe, F; Ohmae, E; Tamegai, H; Nakasone, K
高圧バイオサイエンスとバイオテクノロジー 1 1 47-52 - 121 生物関連高圧研究会 2007年
The psychrophilic, moderately piezophilic bacterium Shewanella violacea strain DSS12 is a deep-sea isolate from a sediment sample collected at the Ryukyu Trench (depth: 5,110 m), which grows optimally at 30 MPa and 8°C but also grows at atmospheric pressure (0.1 MPa) and 8°C. We have examined this strain to elucidate the molecular basis for gene and protein regulations at different pressure conditions because this strain is useful as a model bacterium for comparing the various features of bacterial physiology under pressure conditions. Proteins, from such deep-sea adapted piezophiles, could be active under high-pressure conditions in general. Actually atmospheric pressure adapted proteins can be inactive under higher-pressure conditions. For bio-processing under pressure, people are looking for pressure-tolerant enzymes, thus, “piezophilic proteins” would be focus on such industrial applications. In the case of respiratory proteins, cell divisional protein FtsZ, RNA polymerase subunit structure, and dihydrofolate reductase (DHFR), piezophilic proteins were unique for adaptation to high-pressure environment and some of them were more stable and active under higher pressure conditions.