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

A Gram-positive, strictly aerobic, rod-shaped, non-motile bacterial strain, designated MJ28T, was isolated from a sludge sample from the Daejeon sewage disposal plant in South Korea. A polyphasic approach was applied to study the taxonomic position of strain MJ28T. Strain MJ28T showed highest 16S rRNA gene sequence similarity to Pseudoclavibacter soli KP02T (95.2 %). Levels of 16S rRNA gene sequence similarity to the type strains of other Pseudoclavibacter species were less than 94.0 %. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain MJ28T belonged to the clade formed by members of the genus Pseudoclavibacter in the family Microbacteriaceae. The G+C content of the genomic DNA of strain MJ28T was 65.8 mol%. The chemotaxonomic characteristics of strain MJ28T showed features typical of the genus Pseudoclavibacter, with MK-9 as the predominant respiratory quinone, 2,4-diaminobutryic acid as the diamino acid in the peptidoglycan, and anteiso-C17:0 (44.6 %), anteiso-C15:0 (35.7 %) and C16:0 (9.5 %) as the major fatty acids. On the basis of phylogenetic inference, fatty acid profile and other phenotypic properties, strain MJ28T is considered to represent a novel species of the genus Pseudoclavibacter, for which the name Pseudoclavibacter caeni sp. nov. is proposed. The type strain is MJ28T (=KCTC 19773T=JCM 16921T).