Muriicola marianensis sp. nov., isolated from seawater

Abstract

A Gram-stain-negative, aerobic, orange-pigmented, rod-shaped and non-motile bacterium, designated strain A6B8T, was isolated from seawater of the Mariana Trench. The isolate grew at 4–50 °C (optimum 30–35 °C), at pH 6.5–8.0 (optimum pH 7.5) and with 0.5–4.0 % (w/v) NaCl (optimum 1.0–2.0 %). Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain A6B8T was related most closely to the genus Muriicola and shared highest sequence similarity of 97.7 % with Muriicola jejuensis EM44T. Chemotaxonomic analysis showed menaquinone 6 (MK-6) was the predominant isoprenoid and iso-C15 : 0, iso-C15 : 1 G and iso-C17 : 0 3-OH were the major cellular fatty acids. The polar lipid profile of strain A6B8T included phosphatidylethanolamine, three unidentified aminolipids and four unidentified lipids. The genomic DNA G+C content was 47.1 mol%. The DNA–DNA relatedness value (23.3 %) clearly demonstrated that strains A6B8T and M. jejuensis EM44T were representatives of two different species. Based on the phenotypic, phylogenetic and chemotaxonomic characterizations, A6B8T ( = CGMCC 1.12606T = KCTC 32436T) is considered to be the type strain of a novel species of the genus Muriicola , for which the name Muriicola marianensis sp. nov. is proposed.