Variovorax dokdonensis sp. nov., isolated from soil

Abstract

A Gram-negative, motile and oval- or rod-shaped bacterial strain, DS-43T, was isolated from soil from Dokdo, Korea, and its taxonomic position was investigated by using a polyphasic approach. The strain grew optimally at pH 7·0–8·0 and at 30 °C in the presence of 0·5 % (w/v) NaCl. Strain DS-43T had Q-8 as the predominant ubiquinone and C16 : 0, C16 : 1 ω7c and/or iso-C15 : 0 2-OH, C18 : 1 ω7c and C17 : 0 cyclo as the major fatty acids, which are consistent with the corresponding data for the type strain (KCTC 12459T) of Variovorax paradoxus. The DNA G+C content was 66·0 mol%. Phylogenetic analyses based on 16S rRNA gene sequences showed that strain DS-43T was most closely related to Variovorax paradoxus, the only recognized species of the genus. The level of 16S rRNA gene sequence similarity between strain DS-43T and V. paradoxus IAM 12373T was 97·3 %. DNA–DNA relatedness data and differential phenotypic properties demonstrated that strain DS-43T is distinguishable from V. paradoxus. On the basis of phenotypic, phylogenetic and genetic data, it is proposed that strain DS-43T (=KCTC 12544T=CIP 108838T) be classified in the genus Variovorax as a member of a novel species, Variovorax dokdonensis sp. nov.