Thalassomonas agariperforans sp. nov., an agarolytic bacterium isolated from marine sand

Abstract

A Gram-staining-negative, motile, agarolytic bacterium, designated M-M1(T), was isolated from marine sand obtained from Geoje Island, South Sea, Korea, and its taxonomic position was investigated using a polyphasic taxonomic approach. Strain M-M1(T) grew optimally at pH 7.0-8.0, at 30 °C and in the presence of 2 % (w/v) NaCl. It did not grow in the presence of >7 % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain M-M1(T) fell within the clade comprising members of the genus Thalassomonas, clustering with Thalassomonas agarivorans TMA1(T), Thalassomonas loyana CBMAI 722(T) and Thalassomonas ganghwensis JC2041(T), with which it exhibited 16S rRNA gene sequence similarity values of 96.4, 96.0 and 94.9 % respectively. Strain M-M1(T) exhibited 94.7-95.2 % 16S rRNA gene sequence similarity to the other species of the genus Thalassomonas. Strain M-M1(T) contained Q-8 as the predominant ubiquinone and C(16 : 1)ω7c and/or iso-C(15 : 0) 2-OH, C(16 : 0) and C(18 : 1)ω7c as the major fatty acids. The DNA G+C content was 44.2 mol%. Strain M-M1(T) could be differentiated from phylogenetically related species of the genus Thalassomonas by differences in some phenotypic properties. On the basis of the phenotypic, chemotaxonomic and phylogenetic data, strain M-M1(T) is considered to represent a novel species of the genus Thalassomonas, for which the name Thalassomonas agariperforans sp. nov. is proposed. The type strain is M-M1(T) (= KCTC 23343(T) = CCUG 60020(T)).