Shewanella marisflavi sp. nov. and Shewanella aquimarina sp. nov., slightly halophilic organisms isolated from sea water of the Yellow Sea in Korea

Two Gram-negative, motile, non-spore-forming, rod-shaped organisms, strains SW-117^T and SW-120^T, were isolated from sea water of the Yellow Sea in Korea and subjected to a polyphasic taxonomic study. Strains SW-117^T and SW-120^T simultaneously contained both menaquinones (MK) and ubiquinones (Q) as isoprenoid quinones; the predominant menaquinone was MK-7 and the predominant ubiquinones were Q-7 and Q-8. The major fatty acid detected in the two strains was iso-C_{15 : 0}. The DNA G+C content of strains SW-117^T and SW-120^T was 51 and 54 mol%, respectively. Phylogenetic analyses based on 16S rRNA gene sequences showed that strains SW-117^T and SW-120^T fall within the radiation of the cluster comprising Shewanella species. Strains SW-117^T and SW-120^T showed a 16S rRNA gene sequence similarity of 97·4 % and a DNADNA relatedness level of 10·1 %. Strains SW-117^T and SW-120^T exhibited 16S rRNA gene sequence similarity levels of 93·898·5 % and 92·497·0 %, respectively, to Shewanella species. Strain SW-117^T exhibited DNADNA relatedness levels of 8·320·3 % to the type strains of six phylogenetically related Shewanella species. On the basis of phenotypic, phylogenetic and genetic data, strains SW-117^T and SW-120^T were classified in the genus Shewanella as two distinct novel species, for which the names Shewanella marisflavi sp. nov. (type strain, SW-117^T=KCCM 41822^T=JCM 12192^T) and Shewanella aquimarina sp. nov. (type strain, SW-120^T=KCCM 41821^T=JCM 12193^T) are proposed, respectively.