title: A thermophilic, hydrogenogenic and carboxydotrophic bacterium, Calderihabitans maritimus gen. nov., sp. nov., from a marine sediment core of an undersea caldera.
abstract: A hydrogenogenic, carboxydotrophic marine bacterium, strain KKC1(T), was isolated from a sediment core sample taken from a submerged marine caldera. Cells were non-motile, Gram-stain-negative, 1.0-3.0 µm straight rods, often observed with round endospores. Strain KKC1(T) grew at 55-68 °C, pH 5.2-9.2 and 0.8-14 % (w/v) salinity. Optimum growth occurred at 65 °C, pH 7.0-7.5 and 2.46 % salinity with a doubling time of 3.7 h. The isolate grew chemolithotrophically, producing H2 from carbon monoxide (CO) oxidation with reduction of various electron acceptors, e.g. sulfite, thiosulfate, fumarate, ferric iron and AQDS (9,10-anthraquinone 2,6-disulfonate). KKC1(T) grew heterotrophically on pyruvate, lactate, fumarate, glucose, fructose and mannose with thiosulfate as an electron acceptor. When grown mixotrophically on CO and pyruvate, C16 : 0 constituted almost half of the total cellular fatty acids. The DNA G+C content was 50.6 mol%. The 16S rRNA gene sequence of KKC1(T) was most closely related to those of members of the genus Moorella with similarity ranging from 91 to 89 %. Based on physiological and phylogenetic novelty, we propose the isolate as a representative of a new genus and novel species with the name Calderihabitans maritimus gen. nov., sp. nov.; the type strain of the type species is KKC1(T) ( = DSM 26464(T) = NBRC 109353(T)).
authors.affiliation: Laboratory of Marine Microbiology, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan.
authors.forename: Yasuko
authors.initials: Y
authors.lastname: Yoneda
authors.affiliation: Laboratory of Marine Microbiology, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Yoshida
authors.affiliation: Center for Advance Marine Core Research, Kochi University, Kochi 783-8502, Japan.
authors.forename: Hisato
authors.initials: H
authors.lastname: Yasuda
authors.affiliation: Graduate School of Marine Science and Technology, Tokyo University of Marine Science and Technology, Tokyo 108-8477, Japan.
authors.forename: Chiaki
authors.initials: C
authors.lastname: Imada
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
mesh_terms: D000880:Anthraquinones / Q000378:metabolism; D015373:Bacterial Typing Techniques; D001482:Base Composition; D002248:Carbon Monoxide / Q000378:metabolism; D004269:DNA, Bacterial / Q000235:genetics; D005227:Fatty Acids / Q000032:analysis; D005290:Ferric Compounds / Q000378:metabolism; D005650:Fumarates / Q000378:metabolism; D019015:Geologic Sediments / Q000382:microbiology*; D006863:Hydrogen-Ion Concentration; D008969:Molecular Sequence Data; D058845:Moorella / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification; D010084:Oxidation-Reduction; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012623:Seawater / Q000382:microbiology; D017422:Sequence Analysis, DNA; D013885:Thiosulfates / Q000378:metabolism
chemical_list: D000880:Anthraquinones; D004269:DNA, Bacterial; D005227:Fatty Acids; D005290:Ferric Compounds; D005650:Fumarates; D012336:RNA, Ribosomal, 16S; D013885:Thiosulfates; C408124:anthraquinone-2,6-disulfonate; D002248:Carbon Monoxide