title: Colwellia piezophila sp. nov., a novel piezophilic species from deep-sea sediments of the Japan Trench.
abstract: Two strains of obligately piezophilic bacteria were isolated from sediment collected from the bottom surface of a small canyon on the seaward slope of the Japan Trench at a depth of 6278 m. The isolated strains, Y223GT and Y251E, are closely affiliated with members of the genus Colwellia on the basis of 16S rRNA gene sequence analysis. The G + C contents of both strains were about 39 mol%. DNA-DNA hybridization values between these strains and Colwellia reference strains were significantly lower than those accepted as the phylogenetic definition of a species. The novel strains are Gram-negative, polarly flagellated and facultatively anaerobic. The optimal pressure for growth was 60 MPa at both 4 and 10 degrees C; the most rapid growth rate was observed at 10 degrees C and 60 MPa. No growth occurred at 15 degrees C under any pressure studied. The major isoprenoid quinone is Q-8. The predominant cellular fatty acids are C16 : 0 and C16 : 1. Based on the taxonomic differences observed, the isolated strains appear to represent a novel obligately piezophilic Colwellia species. The name Colwellia piezophila sp. nov. (type strain Y223GT = JCM 11831T = ATCC BAA-637T) is proposed.
authors.affiliation: The DEEPSTAR Group, Japan Marine Science and Technology Center (JAMSTEC), 2-15 Natsushima-cho, Yokosuka 237-0061, Japan.
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Nogi
authors.affiliation: The DEEPSTAR Group, Japan Marine Science and Technology Center (JAMSTEC), 2-15 Natsushima-cho, Yokosuka 237-0061, Japan.
authors.forename: Shoichi
authors.initials: S
authors.lastname: Hosoya
authors.affiliation: Marine Ecosystems Research Department, Japan Marine Science and Technology Center (JAMSTEC), 2-15 Natsushima-cho, Yokosuka 237-0061, Japan.
authors.forename: Chiaki
authors.initials: C
authors.lastname: Kato
authors.affiliation: The DEEPSTAR Group, Japan Marine Science and Technology Center (JAMSTEC), 2-15 Natsushima-cho, Yokosuka 237-0061, Japan.
authors.forename: Koki
authors.initials: K
authors.lastname: Horikoshi
mesh_terms: D000693:Anaerobiosis; D015373:Bacterial Typing Techniques; D001482:Base Composition; D004269:DNA, Bacterial / Q000737:chemistry / Q000302:isolation & purification; D004275:DNA, Ribosomal / Q000737:chemistry / Q000302:isolation & purification; D005227:Fatty Acids / Q000032:analysis; D005407:Flagella; D020563:Gammaproteobacteria / Q000145:classification* / Q000166:cytology / Q000302:isolation & purification* / Q000502:physiology; D020459:Genes, rRNA; D019015:Geologic Sediments / Q000382:microbiology*; D006874:Hydrostatic Pressure; D007564:Japan; D008969:Molecular Sequence Data; D009693:Nucleic Acid Hybridization; D010802:Phylogeny; D011809:Quinones / Q000032:analysis; D012329:RNA, Bacterial / Q000235:genetics; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D013696:Temperature; D014871:Water Microbiology
chemical_list: D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D005227:Fatty Acids; D011809:Quinones; D012329:RNA, Bacterial; D012336:RNA, Ribosomal, 16S