A yellow-pigmented, Gram-stain negative and facultatively anaerobic bacterium, designated MF326(T), was isolated from a sample of sediment collected from a sea cucumber culture pond in Rongcheng, China (122°14'34″E 36°54'36″N). Cells of strain MF326(T) were found to be catalase negative and oxidase positive. Optimal growth was found to occur at 30 °C and pH 7.0-7.5 in the presence of 2.0-3.0% (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain MF326(T) is a member of the genus Mesonia and exhibits the high sequence similarity (94.3%) with the type strain of Mesonia ostreae, followed by Mesonia algae (93.9%). The dominant fatty acids of strain MF326(T) were identified as iso-C(15:0), an unidentified fatty acid with an equivalent chain-length of 13.565 and anteiso-C(15:0). The major polar lipids were found to be two unidentified lipids and phosphatidylethanolamine. The major respiratory quinone was found to be MK-6 and the genomic DNA G+C content was determined to be 40.7 mol%. On the basis of the phylogenetic analysis and differential phenotypic characteristics, it is concluded that strain MF326(T) (=KCTC 42255(T) =MCCC 1H00125(T)) should be assigned to the genus Mesonia as the type strain of a novel species, for which the name Mesonia sediminis sp. nov. is proposed.
Keywords: 16S rRNA gene; Mesonia sediminis sp. nov.; Polyphasic taxonomy; Sediment.