Stenotrophomonas daejeonensis sp. nov., isolated from sewage

Abstract

A Gram-stain-negative, motile, aerobic bacterial strain, designated MJ03(T), was isolated from sewage and was characterized taxonomically by using a polyphasic approach. Comparative 16S rRNA gene sequence analysis showed that strain MJ03(T) belongs to the family Xanthomonadaceae, class Gammaproteobacteria, and was related most closely to Stenotrophomonas acidaminiphila AMX 19(T) (97.9 % sequence similarity), Stenotrophomonas humi R-32729(T) (97.1 %), Stenotrophomonas nitritireducens L2(T) (96.9 %), Stenotrophomonas maltophila ATCC 13637(T) (96.8 %) and Stenotrophomonas terrae R-32768(T) (96.7 %). The G+C content of the genomic DNA of strain MJ03(T) was 64.7 mol%. The detection of a quinone system with ubiquinone Q-8 as the predominant component and a fatty acid profile with iso-C₁₅:₀, iso-C₁₁:₀, iso-C₁₄:₀, iso-C₁₇:₁ω9c, iso-C₁₁:₀ 3-OH and iso-C₁₃:₀ 3-OH as major components supported the affiliation of strain MJ03(T) to the genus Stenotrophomonas. However, levels of DNA-DNA relatedness between strain MJ03(T) and the type strains of five closely related species of the genus Stenotrophomonas ranged from 11 to 34 %, showing clearly that the isolate represents a novel genospecies. Strain MJ03(T) could be differentiated clearly from its phylogenetic neighbours on the basis of several phenotypic, genotypic and chemotaxonomic features. Therefore, strain MJ03(T) is considered to represent a novel species of the genus Stenotrophomonas, for which the name Stenotrophomonas daejeonensis sp. nov. is proposed. The type strain is MJ03(T) (=KCTC 22451(T) =JCM 16244(T)).