|Title||Novel Psychropiezophilic oceanospirillales species Profundimonas piezophila gen. nov., sp nov., isolated from the deep-sea environment of the Puerto Rico Trench|
|Publication Type||Journal Article|
|Year of Publication||2014|
|Authors||Cao Y., Chastain R.A, Eloe E.A, Nogi Y., Kato C., Bartlett DH|
|Journal||Applied and Environmental Microbiology|
|Type of Article||Article|
|Keywords||bacterium; eicosapentaenoic acid; high-pressure; hydrostatic-pressures; low-temperature; mariana trench; neptunomonas; osedax; profundum ss9; shewanella-violacea|
The diversity of deep-sea high-pressure-adapted (piezophilic) microbes in isolated monoculture remains low. In this study, a novel obligately psychropiezophilic bacterium was isolated from seawater collected from the Puerto Rico Trench at a depth of similar to 6,000 m. This isolate, designated YC-1, grew best in a nutrient-rich marine medium, with an optimal growth hydrostatic pressure of 50 MPa (range, 20 to 70 MPa) at 8 degrees C. Under these conditions, the maximum growth rate was extremely slow, 0.017 h(-1), and the maximum yield was 3.51 X 10(7) cells ml(-1). Cell size and shape changed with pressure, shifting from 4.0 to 5.0 mu m in length and 0.5 to 0.8 mu m in width at 60 MPa to 0.8-to 1.0-mu m diameter coccoid cells under 20 MPa, the minimal pressure required for growth. YC-1 is a Gram-negative, facultatively anaerobic heterotroph. Its predominant cellular fatty acids are the monounsaturated fatty acids (MUFAs) C-16:1 and C-18:1 Unlike many other psychropiezophiles, YC-1 does not synthesize any polyunsaturated fatty acids (PUFAs). Phylogenetic analysis placed YC-1 within the family of Oceanospirillaceae, closely related to the uncultured symbiont of the deep-sea whale bone-eating worms of the genus Osedax. In common with some other members of the Oceanospirillales, including those enriched during the Deepwater Horizon oil spill, YC-1 is capable of hydrocarbon utilization. On the basis of its characteristics, YC-1 appears to represent both a new genus and a new species, which we name Profundimonas piezophila gen. nov., sp. nov.