Halomonas xianhensis sp. nov., a moderately halophilic bacterium isolated from a saline soil contaminated with crude oil

A Gram-negative, aerobic, short rod-shaped and non-motile bacterium, strain A-1 ^T, was isolated from a saline soil contaminated with crude oil in Xianhe, Shangdong Province, China. Strain A-1 ^T formed yellow colonies, was moderately halophilic and grew with 0.05-27.5% (w/v) total salts (optimum 5-8 %), at 10-42 °C (optimum 30 °C) and at pH 5.5-9.0 (optimum pH 7.2). The dominant fatty acids (>5%) were C _{16: 0}, summed feature 3 (comprising C _16:1 ω7c and/or iso-C _15:0 2-OH), C _{18: 1} ω7c, C _19:0 cyclo ω 8c and C _{12: 0} 3-OH and the predominant ubiquinone was Q-9. The genomic DNA G+C content was 67.1 mol%. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain A-1 ^T belonged to the genus Halomonas in the class Gammaproteobacteria. The closest relatives were Halomonas lutea YIM 91125 ^T (97.7% 16S rRNA gene sequence similarity), H. muralis LMG 20969 ^T (95.6 %), H. pantelleriensis AAP ^T (95.5 %) and H. kribbensis BH843 ^T (95.2 %). DNA-DNA relatedness between strain A-1 ^T and H. lutea CCTCC AB 206093 ^T was 27±3%. On the basis of phenotypic, chemotaxonomic and phylogenetic features, strain A-1 ^T should be placed in the genus Halomonas as a representative of a novel species. The name Halomonas xianhensis sp. nov. is proposed, with strain A-1 ^T (=CGMCC 1.6848 ^T =JCM 14849 ^T) as the type strain.