Gordonia caeni sp. nov., isolated from sludge of a sewage disposal plant

Abstract

A Gram-stain-positive, strictly aerobic, short-rod-shaped, non-motile strain (designated MJ32(T)) was isolated from a sludge sample of the Daejeon sewage disposal plant in South Korea. A polyphasic approach was applied to study the taxonomic position of strain MJ32(T). Strain MJ32(T) showed highest 16S rRNA gene sequence similarity to Gordonia hirsuta DSM 44140(T) (98.1%) and Gordonia hydrophobica DSM 44015(T) (97.0%); levels of sequence similarity to the type strains of other recognized Gordonia species were less than 97.0%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain MJ32(T) belonged to the clade formed by members of the genus Gordonia in the family Gordoniaceae. The G+C content of the genomic DNA of strain MJ32(T) was 69.2 mol%. Chemotaxonomically, strain MJ32(T) showed features typical of the genus Gordonia. The predominant respiratory quinone was MK-9(H(2)), the mycolic acids present had C(56)-C(60) carbon atoms, and the major fatty acids were C(16:0) (34.6%), tuberculostearic acid (21.8%), C(16:1)ω7c (19.5%) and C(18:1)ω9c (12.7%). The peptidoglycan type was based on meso-2,6-diaminopimelic acid as the diagnostic diamino acid with glycolated sugars. On the basis of phylogenetic inference, fatty acid profile and other phenotypic properties, strain MJ32(T) is considered to represent a novel species of the genus Gordonia, for which the name Gordonia caeni sp. nov. is proposed. The type strain is MJ32(T) (=KCTC 19771(T)=JCM 16923(T)).