Sphingomonas ginsenosidivorax sp. nov., with the ability to transform ginsenosides

A Gram-negative, strictly aerobic, non-motile, non-spore-forming and rod-shaped bacterial strain designated KHI67^T was isolated from sediment of the Gapcheon River in South Korea and its taxonomic position was investigated by using a polyphasic approach. Strain KHI67^T was observed to grow optimally at 25–30 °C and at pH 7.0 on nutrient and R2A agar. On the basis of 16S rRNA gene sequence similarity, strain KHI67^T was shown to belong to the family Sphingomonadaceae and was related to Sphingomonas faeni MA-olki^T (97.6 % sequence similarity), Sphingomonas aerolata NW12^T (97.5 %) and Sphingomonas aurantiaca MA101b^T (97.3 %). The G + C content of the genomic DNA was determined to be 65.6 %. The major ubiquinone was found to be Q-10, the major polyamine was identified as homospermidine and the major fatty acids identified were summed feature 8 (comprising C_18:1 ω7c/ω6c; 37.0 %), C_16:0 (13.0 %), summed feature 3 (comprising C_16:1 ω7c/C_16:1 ω6c; 12.8 %) and C_14:0 2OH (9.3 %). DNA and chemotaxonomic data supported the affiliation of strain KHI67^T to the genus Sphingomonas. The DNA–DNA relatedness values between strain KHI67^T and its closest phylogenetic neighbours were below 15 %. Strain KHI67^T could be differentiated genotypically and phenotypically from the recognised species of the genus Sphingomonas. The isolate therefore represents a novel species, for which the name Sphingomonas ginsenosidivorax sp. nov. is proposed, with the type strain KHI67^T (=KACC 14951^T = JCM 17076^T = LMG 25801^T).