Halomonas marinisediminis sp. nov., A Moderately Halophilic Bacterium Isolated from the Bohai Gulf.

Abstract

A novel Gram-stain-negative, moderately halophilic bacterium, designated strain 204T, was isolated from a marine sediment sample in the Bohai Gulf, Yellow Sea, China. Cells of strain 204T are aerobic, motile, cocci or short rods with two lateral flagella. Growth was observed at 15-40°C (optimum, 30°C), pH 6.0-9.0 (optimum, 7.0-7.5) and in the presence of 1.0-18.0% (w/v) NaCl (optimum, 3.0-8.0%). Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain 204T belonged to the genus Halomonas, showing highest sequence similarity to Halomonas alimentaria YKJ-16T (98.08%), followed by Halomonas sediminicola (97.47%), Halomonas fontilapidosi (97.14%), Halomonas halodenitrificans (96.98%), Halomonas ventosae (96.92%), and Halomonas shengliensis (96.85%). The draft genome is 3.8Mb in length, containing 3673 protein-coding genes, 62 tRNA genes and 10 rRNA genes, and DNA G+C content is 62.7mol%. Strain 204T contains phosphatidylglycerol, phosphatidylethanolamine, and diphosphatidylglycerol as the main polar lipids, and the predominant respiratory quinone was ubiquinone Q-9. The major cellular fatty acids (> 5%) are C18:1ω7c, C16:1ω7cand/or C16:1ω6c, C16:0 and C12:03-OH. Strain 204T was clearly distinguished from the closely related type strains through phylogenetic analysis, dDNA-DNA hybridization, fatty acid composition data and a range of physiological and biochemical characteristics comparisons. On the basis of the polyphasic analysis, strain 204T is considered to represent a novel species of the genusHalomonas, for which the nameHalomonas marinisediminissp. nov. is proposed. The type strain is 204T (= MCCC 1H00366T = KCTC 62957T).