Halomonas sediminis sp. nov., a new halophilic bacterium isolated from salt-lake sediment in China.

A novel Gram-negative, slightly halophilic, catalase- and oxidase-positive, obligately aerobic bacterium, strain YIM-C248(T), was isolated from a sediment sample collected from a salt-lake in the Qaidam Basin in Qinghai, north-west China. Cells were non-sporulating short rods, occurring singly or as doublets, motile with peritrichous flagella. Growth occurred with 1-15% (w/v) NaCl [optimum 2-4% (w/v) NaCl], at pH 6.0-10.0 (optimum pH 7.5) and at 4-35 degrees C (optimum 25-30 degrees C). The major cellular fatty acids were C(18:1) omega 7c, C(12:0) 3-OH, cyclo C(19:0) omega 8c, C(16:0) and C(16:1). The predominant respiratory quinone was Q-9 and the genomic DNA G + C content was 58.6 mol%. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain YIM-C248(T) should be assigned to the genus Halomonas. The sequence similarities between the isolate and the type strains of members of the genus Halomonas were in the range of 92.5-97.5%. The combination of phylogenetic analysis, DNA-DNA hybridization data, phenotypic characteristics and chemotaxonomic differences supported the view that strain YIM-C248(T) represents a new species of the genus Halomonas, for which the name Halomonas sediminis sp. nov. is proposed, with YIM-C248(T) (=CCTCC AA 207031 = KCTC 22167) as the type strain.