Dokdonella kunshanensis sp. nov., isolated from activated sludge, and emended description of the genus Dokdonella.

A gram-negative, aerobic, non-motile, non-spore-forming rod, designated DC-3(T), was isolated from activated sludge of a wastewater treatment plant in China. Comparative 16S rRNA gene sequence analysis showed that strain DC-3(T) belonged to the family Xanthomonadaceae and formed a lineage within the genus Dokdonella. Strain DC-3(T) shared the highest 16S rRNA gene sequence similarity with Dokdonella soli KIS28-6(T) (97.1 %) and Dokdonella fugitiva A3(T) (97.1 %). The G+C content of the genomic DNA was 71.5 mol%. The major respiratory quinone was Q-8 and the major fatty acids were iso-C17 : 1ω9c (31.6 %), iso-C15 : 0 (12.6 %), iso-C16 : 0 (21.3 %), iso-C17 : 0 (13.1 %) and iso-C11 : 0 3-OH (6.5 %), which supported the affiliation of strain DC-3(T) with the genus Dokdonella. DNA-DNA relatedness between strain DC-3(T) and its closest phylogenetic neighbours was <30 %. The results of physiological and biochemical tests allowed genotypic and phenotypic differentiation of strain DC-3(T) from the recognized species of the genus Dokdonella. On the basis of its phenotypic properties and phylogenetic distinctiveness, strain DC-3(T) represents a novel species of the genus Dokdonella, for which the name Dokdonella kunshanensis sp. nov. is proposed. The type strain is DC-3(T) ( = CCTCC AB 2011179(T)  = KACC 16511(T)). The description of the genus Dokdonella is also emended.