Abstract

A Gram-negative, aerobic, non-spore-forming, motile and ovoid or rod-shaped bacterial strain, designated MA2-16T, was isolated from ark shell (Scapharca broughtonii) collected from the South Sea, South Korea. Strain MA2-16T was found to grow optimally at 30캜, at pH 7.0?.0 and in the presence of 2.0% (w/v) NaCl. Neighbour-joining, maximum-likelihood and maximum-parsimony phylogenetic trees based on 16S rRNA gene sequences revealed that strain MA2-16T clustered with the type strain of Sedimentitalea nanhaiensis. The novel strain exhibited a 16S rRNA gene sequence similarity value of 97.1% to the type strain of S. nanhaiensis. In the neighbour- joining phylogenetic tree based on gyrB sequences, strain MA2-16T formed an evolutionary lineage independent of those of other taxa. Strain MA2-16T contained Q-10 as the predominant ubiquinone and C18:1 ?c and 11-methyl C18:1 ?c as the major fatty acids. The major polar lipids of strain MA2-16T were phosphatidylcholine, phosphatidylglycerol, phosphatidylethanolamine, an unidentified aminolipid and an unidentified lipid. The DNA G+C content of strain MA2- 16T was 57.7 mol% and its DNA-DNA relatedness values with the type strains of S. nanhaiensis and some phylogenetically related species of the genera Leisingera and Phaeobacter were 13?4%. On the basis of the data presented, strain MA2-16T is considered to represent a novel genus and novel species within the family Rhodobacteraceae, for which the name Aliisedimentitalea scapharcae gen. nov., sp. nov. is proposed. The type strain is MA2-16T (=KCTC 42119T =CECT 8598T).

• Keywords: ark shell; Scapharca broughtonii; polyphasic taxonomy; novel genus and species; Aliisedimentitalea scapharcae