title: Characterization of Symbiobacterium toebii, an obligate commensal thermophile isolated from compost.
abstract: A symbiotic thermophilic bacterium, strain SC-1, was isolated from hay compost (toebi) in Korea. The new isolate exhibited an obligate commensal interaction with a thermophilic Geobacillus strain and required crude extracts and/or culture supernatant from Geobacillus sp. SK-1 for axenic growth. The growth factors from Geobacillus sp. SK-1 were irreversibly inactivated by phenol or protease treatment, suggesting that they might be proteins. The cells of strain SC-1 were non-spore forming, nonmotile rods that were stained Gram-negatively. The isolate was a microaerophilic heterotroph. Growth was observed between 45 degrees and 70 degrees C (optimum: 60 degrees C; 2.4-h doubling time) and pH 6.0 and 9.0 (optimum: pH 7.5). The G+C content of the genomic DNA was 65 mol%, and the major quinones were MK-6 and MK-7. A phylogenetic analysis of its 16S rDNA sequence indicated that strain SC-1 is closely related to Symbiobacterium thermophilum and so was named Symbiobacterium toebii on the basis of its physiological and molecular properties.
authors.affiliation: Microbial Genomics Lab., Korea Research Institute of Bioscience and Biotechnology (KRIBB), Yusong, Daejeon.
authors.forename: Sung-Keun
authors.initials: SK
authors.lastname: Rhee
authors.forename: Che Ok
authors.initials: CO
authors.lastname: Jeon
authors.forename: Jin-Woo
authors.initials: JW
authors.lastname: Bae
authors.forename: Kwang
authors.initials: K
authors.lastname: Kim
authors.forename: Jae Jun
authors.initials: JJ
authors.lastname: Song
authors.forename: Joong-Jae
authors.initials: JJ
authors.lastname: Kim
authors.forename: Seung-Goo
authors.initials: SG
authors.lastname: Lee
authors.forename: Hong-Ik
authors.initials: HI
authors.lastname: Kim
authors.forename: Seung-Pyo
authors.initials: SP
authors.lastname: Hong
authors.forename: Yoon-Ho
authors.initials: YH
authors.lastname: Choi
authors.forename: Su-Mi
authors.initials: SM
authors.lastname: Kim
authors.forename: Moon-Hee
authors.initials: MH
authors.lastname: Sung
mesh_terms: D039903:Actinobacteria / Q000145:classification* / Q000254:growth & development / Q000302:isolation & purification; D001419:Bacteria / Q000145:classification; D001482:Base Composition; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D006358:Hot Temperature; D008854:Microscopy, Electron; D008969:Molecular Sequence Data; D010802:Phylogeny; D012037:Refuse Disposal
chemical_list: D004269:DNA, Bacterial