title: Carboxydothermus pertinax sp. nov., a thermophilic, hydrogenogenic, Fe(III)-reducing, sulfur-reducing carboxydotrophic bacterium from an acidic hot spring.
abstract: A novel anaerobic, Fe(III)-reducing, hydrogenogenic, carboxydotrophic bacterium, designated strain Ug1(T), was isolated from a volcanic acidic hot spring in southern Kyushu Island, Japan. Cells of the isolate were rod-shaped (1.0-3.0 µm long) and motile due to peritrichous flagella. Strain Ug1(T) grew chemolithoautotrophically on CO (100% in the gas phase) with reduction of ferric citrate, amorphous iron (III) oxide, 9,10-anthraquinone 2,6-disulfonate, thiosulfate or elemental sulfur. No carboxydotrophic growth occurred with sulfate, sulfite, nitrate or fumarate as electron acceptor. During growth on CO, H(2) and CO(2) were produced. Growth occurred on molecular hydrogen as an energy source and carbon dioxide as a sole carbon source. Growth was observed on various organic compounds under an N(2) atmosphere with the reduction of ferric iron. The temperature range for carboxydotrophic growth was 50-70 °C, with an optimum at 65 °C. The pH(25 °C) range for growth was 4.6-8.6, with an optimum between 6.0 and 6.5. The doubling time under optimum conditions using CO with ferric citrate was 1.5 h. The DNA G+C content was 42.2 mol%. Analysis of 16S rRNA gene sequences demonstrated that this strain belongs to the thermophilic carboxydotrophic bacterial genus Carboxydothermus, with sequence similarities of 94.1-96.6% to members of this genus. The isolate can be distinguished from other members of the genus Carboxydothermus by its ability to grow with elemental sulfur or thiosulfate coupled to CO oxidation. On the basis of phylogenetic analysis and unique physiological features, the isolate represents a novel species of the genus Carboxydothermus for which the name Carboxydothermus pertinax sp. nov. is proposed; the type strain of the novel species is Ug1(T) (=DSM 23698(T)=NBRC 107576(T)).
authors: Laboratory of Marine Microbiology, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan.
authors: Yasuko
authors: Y
authors: Yoneda
authors: Laboratory of Marine Microbiology, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan.
authors: Takashi
authors: T
authors: Yoshida
authors: Laboratory of Marine Microbiology, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan.
authors: Satoshi
authors: S
authors: Kawaichi
authors: Laboratory of Marine Microbiology, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan.
authors: Takashi
authors: T
authors: Daifuku
authors: Laboratory of Tree Cell Biology, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan.
authors: Keiji
authors: K
authors: Takabe
authors: Laboratory of Marine Microbiology, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan.
authors: Yoshihiko
authors: Y
authors: Sako
mesh_terms: D000693:Anaerobiosis; D015373:Bacterial Typing Techniques; D001482:Base Composition; D002245:Carbon Dioxide / Q000378:metabolism; D002248:Carbon Monoxide / Q000378:metabolism*; D016000:Cluster Analysis; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D005407:Flagella / Q000502:physiology; D006094:Gram-Positive Bacteria / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D045482:Hot Springs / Q000382:microbiology*; D006859:Hydrogen / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D007501:Iron / Q000378:metabolism*; D007564:Japan; D008969:Molecular Sequence Data; D010084:Oxidation-Reduction; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D013455:Sulfur / Q000378:metabolism*; D013696:Temperature
chemical_list: D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D012336:RNA, Ribosomal, 16S; D002245:Carbon Dioxide; D013455:Sulfur; D002248:Carbon Monoxide; D006859:Hydrogen; D007501:Iron