Muricauda flavescens sp. nov. and Muricauda aquimarina sp. nov., isolated from a salt lake near Hwajinpo Beach of the East Sea in Korea, and emended description of the genus Muricauda

Four Gram-negative, non-spore-forming, slightly halophilic rods (strains SW-62(T), SW-74, SW-63(T) and SW-72) with appendages were isolated from a salt lake near Hwajinpo Beach on the East Sea in Korea, and subjected to a polyphasic taxonomic analysis. Phylogenetic analyses based on 16S rRNA gene sequences showed that strains SW-62(T), SW-74, SW-63(T) and SW-72 formed a coherent cluster with Muricauda ruestringensis. Strains SW-62(T) and SW-74 had the same 16S rRNA gene sequence, as did strains SW-63(T) and SW-72. The level of 16S rRNA gene sequence similarity between strains SW-62(T) and SW-63(T) was 97.0 %. Strains SW-62(T) and SW-63(T) exhibited 16S rRNA gene similarity levels of 96.5 and 98.3 %, respectively, with respect to M. ruestringensis DSM 13258(T). The predominant isoprenoid quinone found in the four isolates and M. ruestringensis DSM 13258(T) was MK-6. The four strains contained iso-C(17 : 0) 3-OH, iso-C(15 : 1) and iso-C(15 : 0) as the major fatty acids. Their DNA G + C contents were 44.1-45.4 mol%. The levels of DNA-DNA relatedness indicated that strains SW-62(T) and SW-74 and strains SW-63(T) and SW-72 were members of two species that were different from M. ruestringensis. On the basis of phenotypic and phylogenetic data and genomic distinctiveness, strains SW-62(T) and SW-74 and strains SW-63(T) and SW-72 were placed in the genus Muricauda as two distinct novel species, for which the names Muricauda flavescens sp. nov. (type strain, SW-62(T) = KCCM 41645(T) = JCM 11812(T)) and Muricauda aquimarina sp. nov. (type strain, SW-63(T) = KCCM 41646(T) = JCM 11811(T)), respectively, are proposed.