Microbacterium paludicola sp nov., a novel xylanolytic bacterium isolated from swamp forest

Abstract

A xylanolytic bacterium, US15(T), was isolated from swamp forest soil in Ulsan, Korea. The cells of the novel strain were Gram-positive, non-motile, short-rod-shaped and showed chemotaxonomic properties that were consistent with its classification in the genus Microbacterium. Chemotaxonomic results showed MK-12 and MK-11 as major menaquinones, predominating iso- and anteiso-branched cellular fatty acids, glucose, galactose and mannose as cell-wall sugars, peptidoglycan-type B2 beta with glycolyl residues and a DNA G+C content of 66.5 mol%. Phylogenetic analysis based on 16S rRNA gene sequencing showed that strain US15T was closely related to Microbacterium arborescens IFO 3750(T), Microbacterium imperiale IFO 12610(T) and Microbacterium ulmi LMG 20991(T) (96.9, 96.8 and 96.2% similarities, respectively), and formed a separate lineage within the genus Microbacterium. Combined genotypic and phenotypic data showed that strain US15(T) (=DSM 16915(T)=KCTC 19080(T)) merits recognition as the type strain of a novel species within the genus Microbacterium, for which the name Microbacterium paludicola sp. nov. is proposed.