The taxonomic status of a Gram-reaction-negative, aerobic, motile, rod-shaped bacterium, designated strain GH3-15T, was examined by a polyphasic approach. The strain, which was isolated from the rhizosphere mudflat of a halophyte at the seashore of Gangwha Island, Republic of Korea, was found to belong to the family Erythrobacteraceae based on 16S rRNA gene sequences. The closest phylogenetic neighbour was Erythrobacter xanthus SM1501T (98.3 % sequence similarity). Levels of 16S rRNA gene sequence similarity of strain GH3-15T to other members of the family Erythrobacteracae were <97.1 %. The respiratory quinone was Q-10. The major fatty acids were C17 : 1ω6c, C18 : 1ω7c, C15 : 0 2-OH, 11-methyl C18 : 1ω7c and C17 : 0. The polar lipids were phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol and sphingoglycolipid. The novel isolate exhibited growth at 20-40 °C, at pH 5-9, and in the presence of 1-7 % (w/v) NaCl. DNA relatedness between strain GH3-15T and its closet relative was 32.9±8.8 %. On the basis of phenotypic, chemotaxonomic and DNA-DNA hybridization data, in addition to a distinct phylogenetic position, strain GH3-15T (=KCTC 62380T=JCM 32445T) represents a novel species of the genus Erythrobacter, for which the name Erythrobactersuaedae sp. nov. is proposed.
Keywords: Erythrobacter suaedae; Suaeda japonica; halophyte; polyphasic analysis; rhizosphere mudflat.