Roseovarius halotolerans sp. nov., isolated from deep seawater

1 Department of Microbiology and Biotechnology Research Institute, Chungbuk National University, Cheongju 361-763, Chungbuk, Republic of Korea 2 Department of Biological Sciences, Korea Advanced Institute of Science and Technology, 373-1 Guseong-dong, Yuseong-gu, Daejeon 305-701, Republic of Korea 3 School of Electrical and Computer Engineering, Chungbuk National University, Cheongju 361-763, Chungbuk, Republic of Korea 4 Yeongnam Agricultural Research Institute (NICS, RDA), Milyang 627-803, Republic of Korea Correspondence Dong-Hyun Roh dhroh{at}chungbuk.ac.kr A Gram-reaction-negative, non-motile, aerobic bacterium, designated HJ50 T , was isolated from deep seawater of the East Sea, South Korea. Cells were ovoid to rod-shaped (0.5–0.8 x 1.3–3.0 µm), often with unequal ends, suggesting a budding mode of reproduction. The strain had an absolute requirement for sea salts and tolerated up to 20 % (w/v) sea salts. Propionate, DL -lactate, 2-ketogluconate, 3-hydroxybutyrate and rhamnose were used as growth substrates, but not mannitol, salicin, 4-hydroxybenzoate or acetate. The major fatty acid was summed feature 7 (C 18 : 1 7 c / 9 t / 12 t ) and the DNA G+C content was 59.0±0.1 mol%. Phylogenetic analyses based on 16S rRNA gene sequences showed that this strain was affiliated with the genus Roseovarius . Similarities between the 16S rRNA gene sequence of strain HJ50 T (1430 nt) and those of type strains of members of the genus Roseovarius were 94.1–96.3 %. DNA–DNA relatedness values between strain HJ50 T and the type strains of members of the genus Roseovarius were low (1.3–24.6 %). Physiological and biochemical differences support assignment of strain HJ50 T to the genus Roseovarius as a representative of a novel species. The name Roseovarius halotolerans sp. nov. is proposed, with HJ50 T (=KCTC 22224 T =LMG 24468 T ) as the type strain. The GenBank/EMBL/DDBJ accession number for the 16S rRNA gene sequence of strain HJ50 T is EU431217 . A TLC showing the polar lipids of strain HJ50 T is available as supplementary material with the online version of this paper.