Microbacterium ginsengiterrae sp. nov., a β-glucosidase-producing bacterium isolated from soil of a ginseng field

Abstract

Strain DCY37T was isolated from a soil sample of a ginseng field in the Republic of Korea and characterized in order to determine its taxonomic position. Cells were Gram-staining-positive, heterotrophic, strictly aerobic, non-motile short rods. 16S rRNA gene sequence analysis revealed that strain DCY37T belongs to the genus Microbacterium. According to 16S rRNA gene sequence analysis, it is closely related to Microbacterium aerolatum DSM 14217T (98.8 %), Microbacterium hydrocarbonoxydans DSM 16089T (98.5 %), Microbacterium natoriense JCM 12611T (98.5 %), Microbacterium foliorum (98.4 %) and Microbacterium phyllosphaerae (98.3 %). However, DNA–DNA hybridization studies showed reassociation values of less than 70 % between representative strains and DCY37T. The DNA G+C content was 64.5 mol%. Strain DCY37T possessed chemotaxonomic markers that were consistent with classification in the genus Microbacterium, i.e. MK-12 and MK-13 as the major menaquinones and anteiso-C15 : 0, anteiso-C17 : 0 and iso-C16 : 0 as the predominant cellular fatty acids. The major cell wall sugars were ribose, xylose and galactose. The diamino acid in cell-wall hydrolysates of strain DCY37T was ornithine and major cell-wall amino acids were alanine, glycine, d-glutamic acid and serine. The major polar lipids were glycolipid, phosphatidylglycerol, diphosphatidylglycerol and unknown aminolipids. Based on these data, DCY37T (=KCTC 19526T =JCM 15516T) should be classified as the type strain of a novel species of the genus Microbacterium, for which the name Microbacterium ginsengiterrae sp. nov. is proposed.