Rhodanobacter rhizosphaerae sp. nov., isolated from soil of ginseng rhizosphere.

A Gram-stain-negative, aerobic, non-motile, non-spore-forming, yellow and rod-shaped bacterium, designated strain CR164T, was isolated from the rhizosphere soil of a ginseng field at Geumsan in Korea. CR164T grew at between 15 and 37 °C (optimal growth at 28 °C), between pH 6.0 and 9.0 (optimal growth at pH 7.0) and at salinities of 0-1.0 % (w/v) NaCl, growing optimally in the absence of NaCl. The results of phylogenetic analyses based on 16S rRNA gene sequences indicated that CR164T represents a member of the genus Rhodanobacter, showing the highest sequence similarity to Rhodanobactercaeni MJ01T (98.5 %), Rhodanobacter ginsenosidimutans Gsoil 3054T (98.4 %), Rhodanobacter thiooxydans LCS2T (98.3 %), Rhodanobacter lindaniclasticus RP5557T (98.1 %), Rhodanobacter denitrificans 2APBS1T (98.0 %), Rhodanobacter fulvus Jip2T (97.6 %), Rhodanobacter soli DCY45T (97.3 %) and 'Rhodanobacterxiangquanii' BJQ-6 (97.0 %). The major fatty acids were iso-C17 : 1ω9c (21.8 %), iso-C15 : 0 (12.1 %), iso-C11 : 0 (11.9 %) and iso-C16 : 0 (11.1 %). The predominant ubiquinone was Q-8. The major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylglycerol. The G+C content of the genomic DNA was 62.3 mol%. DNA-DNA relatedness between CR164T and the type strains of eight other species of the genus ranged from 51 to 9 %. On the basis of the polyphasic analysis, CR164T represents a novel species of the genus Rhodanobacter, for which the name Rhodanobacter rhizosphaerae sp. nov. is proposed. The type strain is CR164T (=KACC 18699T=NBRC 111845T).