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, C16:1ω7c and/or iso-C15:0 2-OH, C18:1ω7c 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.