Sphingobacterium wenxiniae sp. nov., a cypermethrin-degrading species from activated sludge

Abstract

A Gram-negative, non-motile, non-spore-forming, non-flagellated rod capable of degrading cypermethrin, designated LQY-18T, was isolated from activated sludge of a wastewater treatment plant in China. Strain LQY-18T grew at 8–40 °C (optimum 30 °C), at pH 5.0–10.0 (optimum pH 7.0) and with 0–5 % (w/v) NaCl (optimum 1 %). The predominant menaquinone was MK-7 (97 %) and the major fatty acids were summed feature 3 (comprising C16 : 1ω6c and/or C16 : 1ω7c), iso-C15 : 0 and iso-C17 : 0 3-OH. The DNA G+C content was 40.3 mol%. Phylogenetic analysis revealed that the isolate belonged to the genus Sphingobacterium of the phylum Bacteroidetes and showed low 16S rRNA gene sequence similarity with recognized members of the genus Sphingobacterium. The closest neighbour was Sphingobacterium mizutaii ATCC 33299T (92.9 % 16S rRNA gene sequence similarity). On the basis of phenotypic, genetic and phylogenetic data, strain LQY-18T ( = ACCC 05410T = CCTCC AB 2010005T = KCTC 23009T) should be classified as a representative of a novel species of the genus Sphingobacterium, for which the name Sphingobacterium wenxiniae sp. nov. is proposed.