title: Rhodothermus profundi sp. nov., a thermophilic bacterium isolated from a deep-sea hydrothermal vent in the Pacific Ocean.
abstract: Nine thermophilic strains of aerobic, non-sporulating, heterotrophic bacteria were isolated after enrichment of chimney material sampled from a deep-sea hydrothermal field at a depth of 2634m on the East-Pacific Rise (1 °N). The bacteria stained Gram-negative. They were rod-shaped and measured approximately 0.5μm in width and 1.5-3.5μm in length. They grew at 55-80°C, pH 6-8 and 1-6 % NaCl. Optimal growth was observed at 70-75°C, pH7.0 and 1-3 % NaCl. The organisms were identified as members of the genus Rhodothermus, having a 16S rRNA gene similarity of 98.1 % with Rhodothermus marinus DSM 4252(T). The novel isolates differed morphologically, physiologically and chemotaxonomically from R. marinus, e.g. in lack of pigmentation, response to hydrostatic pressure, maximum growth temperature and DNA G+C content. DNA-DNA hybridization revealed a reassociation value of 37.2 % between strain PRI 2902(T) and R. marinus DSM 4252(T), which strongly suggested that they represent different species. Furthermore, AFLP fingerprinting separated the novel strains from R. marinus reference strains. It is therefore concluded that the strains described here should be classified as representatives of a novel species for which the name Rhodothermus profundi sp. nov. is proposed; the type strain is PRI 2902(T) (=DSM 22212(T) =JCM 15944(T)).
authors.affiliation: Matis Vinlandsleid 12, IS-113, Reykjavik, Iceland.
authors.forename: Viggó Thór
authors.initials: VT
authors.lastname: Marteinsson
authors.affiliation: Institute of Biology, University of Iceland, Sturlugata 7, IS-101, Reykjavik, Iceland.|Matis Vinlandsleid 12, IS-113, Reykjavik, Iceland.
authors.forename: Snaedis H
authors.initials: SH
authors.lastname: Bjornsdottir
authors.affiliation: UMR 6197, Centre National de la Recherche Scientifique, Université de Bretagne Occidentale, Ifremer, IUEM, BP70, 29282 Plouzané, France.
authors.forename: Nadège
authors.initials: N
authors.lastname: Bienvenu
authors.affiliation: Arkea Technology Park, Reykir, PO Box 200, IS-810 Hveragerdi, Iceland.
authors.forename: Jakob K
authors.initials: JK
authors.lastname: Kristjansson
authors.affiliation: UMR 6197, Centre National de la Recherche Scientifique, Université de Bretagne Occidentale, Ifremer, IUEM, BP70, 29282 Plouzané, France.
authors.forename: Jean-Louis
authors.initials: JL
authors.lastname: Birrien
mesh_terms: D054458:Amplified Fragment Length Polymorphism Analysis; D015373:Bacterial Typing Techniques; D001482:Base Composition; D004269:DNA, Bacterial / Q000235:genetics; D005227:Fatty Acids / Q000737:chemistry; D060086:Hydrothermal Vents / Q000382:microbiology*; D008969:Molecular Sequence Data; D021141:Nucleic Acid Amplification Techniques; D010140:Pacific Ocean; D010743:Phospholipids / Q000737:chemistry; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D045245:Rhodothermus / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification; D012623:Seawater / Q000382:microbiology*; D017422:Sequence Analysis, DNA; D024482:Vitamin K 2 / Q000031:analogs & derivatives / Q000737:chemistry
chemical_list: D004269:DNA, Bacterial; D005227:Fatty Acids; D010743:Phospholipids; D012336:RNA, Ribosomal, 16S; D024482:Vitamin K 2; C062629:menaquinone 7