title: Caldisphaera lagunensis gen. nov., sp. nov., a novel thermoacidophilic crenarchaeote isolated from a hot spring at Mt Maquiling, Philippines.
abstract: Four novel, thermoacidophilic, crenarchaeotic cocci that grew anaerobically and heterotrophically were isolated from an acidic hot spring in the Philippines; two representative strains were characterized in detail. Most cells were regular cocci, 0.8-1.1 microm in width, which occurred singly or in pairs. They were non-motile and grew at 45-80 degrees C (optimum 70-75 degrees C) and pH 2.3-5.4 (optimum 3.5-4.0). They utilized starch, glycogen, gelatin, beef extract, yeast extract and peptone as carbon and energy sources. Growth was stimulated by the presence of sulfur as an electron acceptor. The lipid fraction contained cyclic and acyclic tetraether core lipids. The DNA G + C content was 31 mol%; phylogenetic analysis based on 16S rDNA sequences showed that the novel cocci represent an independent lineage in the phylum Crenarchaeota, distantly related to Acidilobus aceticus and an allied strain, NC12. Caldisphaera lagunensis gen. nov., sp. nov. is proposed to accommodate the four strains. The type strain is IC-154T (=JCM 11604T=MCC-UPLB 1331T=ANMR 0165T).
authors.affiliation: Japan Collection of Microorganisms, RIKEN (Institute of Physical and Chemical Research), Wako-shi, Saitama 351-0198, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Itoh
authors.affiliation: Biological Resource Center, Biotechnology Center, National Institute of Technology and Evaluation, Kazusa-Kamatari, Kisarazu, Chiba 292-0812, Japan.|Japan Collection of Microorganisms, RIKEN (Institute of Physical and Chemical Research), Wako-shi, Saitama 351-0198, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Suzuki
authors.affiliation: Museum of Natural History, University of the Philippines Los Baños College, Laguna 4031, Philippines.
authors.forename: P C
authors.initials: PC
authors.lastname: Sanchez
authors.affiliation: Laboratory of Microbiology, Department of Applied Biology and Chemistry, Faculty of Applied Bioscience, Tokyo University of Agriculture, Sakuragaoka, Setagaya-ku, Tokyo 156-8502, Japan.|Japan Collection of Microorganisms, RIKEN (Institute of Physical and Chemical Research), Wako-shi, Saitama 351-0198, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Nakase
mesh_terms: D001482:Base Composition; D019615:Crenarchaeota / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D019641:DNA, Archaeal / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000235:genetics; D005618:Fresh Water / Q000382:microbiology; D006358:Hot Temperature; D008854:Microscopy, Electron; D008969:Molecular Sequence Data; D010641:Phenotype; D010679:Philippines; D010802:Phylogeny; D019642:RNA, Archaeal / Q000235:genetics; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D009626:Terminology as Topic
chemical_list: D019641:DNA, Archaeal; D004275:DNA, Ribosomal; D019642:RNA, Archaeal; D012336:RNA, Ribosomal, 16S