title: Marinithermus hydrothermalis gen. nov., sp. nov., a strictly aerobic, thermophilic bacterium from a deep-sea hydrothermal vent chimney.
abstract: A novel thermophilic marine bacterium, designated strain T1T, was isolated from a deep-sea hydrothermal vent chimney sample collected from the Suiyo Seamount in the Izu-Bonin Arc, Japan, at a depth of 1,385 m. Cells of strain T1T were rod-shaped, occurring in pairs or filamentous, and stained Gram-negative. Growth was observed between 50.0 and 72.5 degrees C (optimum 67.5 degrees C; 30 min doubling time) and at pH 6.25-7.75 (optimum pH 7.00). The isolate absolutely required NaCl, at a concentration of 0.5-4.5% (optimum 30%). It was a strictly aerobic heterotroph capable of growing solely on complex organic substrates such as yeast extract, tryptone and Casamino acids, utilizing glutamate, proline, serine, cellobiose, trehalose, sucrose, acetate and pyruvate as complementary substrates. The G+C content of the genomic DNA was 68.6 mol%. The 16S rRNA gene sequence of the isolate was most similar to those from members of the genus Thermus, but the isolate was distantly related to them at the genus level (<90%). In addition, phylogenetic analysis indicated that the isolate was on a novel lineage, deeply branched prior to divergence of the genus Thermus. On the basis of phylogenetic analysis and physiological traits of the isolate, it should be described as a member of a novel genus distinct from the previously described genus Thermus. The name Marinithermus gen. nov. is proposed, with Marinithermus hydrothermalis gen. nov., sp. nov. as the type species. The type strain of M. hydrothermalis gen. nov., sp. nov. is strain T1T (=JCM 11576T =DSM 14884T).
authors.affiliation: Laboratory of Marine Microbiology, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan.
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Sako
authors.affiliation: Laboratory of Marine Microbiology, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Nakagawa
authors.affiliation: Subground Animalcules Retrieval (SUGAR) Project, Frontier Research System for Extremophiles, Japan Marine Science & Technology Center, 2-15 Natsushima-cho, Yokosuka 237-0061, Japan.
authors.forename: Ken
authors.initials: K
authors.lastname: Takai
authors.affiliation: Subground Animalcules Retrieval (SUGAR) Project, Frontier Research System for Extremophiles, Japan Marine Science & Technology Center, 2-15 Natsushima-cho, Yokosuka 237-0061, Japan.
authors.forename: Koki
authors.initials: K
authors.lastname: Horikoshi
mesh_terms: D001482:Base Composition; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000235:genetics; D017753:Ecosystem; D005227:Fatty Acids / Q000032:analysis; D016946:Gram-Negative Aerobic Rods and Cocci / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D006358:Hot Temperature; D007564:Japan; D008854:Microscopy, Electron; D008969:Molecular Sequence Data; D010802:Phylogeny; D011809:Quinones / Q000032:analysis; D012329:RNA, Bacterial / Q000235:genetics; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012623:Seawater / Q000382:microbiology
chemical_list: D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D005227:Fatty Acids; D011809:Quinones; D012329:RNA, Bacterial; D012336:RNA, Ribosomal, 16S