Microbacterium kribbense sp. nov. isolated from soil

Abstract

A Gram-positive, short, rod-shaped, cream-coloured actinobacterium, designated MSL-04T, was isolated from a soil sample collected from an agricultural field on Bigeum Island (Republic of Korea) and was subjected to polyphasic characterization to unravel its taxonomic position. The optimum growth temperature and pH were 28-30 °C and pH 7.2-7.4. Chemotaxonomic characteristics such as B2β-type peptidoglycan with glycolyl residues, MK-11 and MK-12 as the major menaquinones and a fatty acid profile containing iso- and anteiso-branched fatty acids placed this organism within the genus Microbacterium. Phylogenetic analysis based on 16S rRNA gene sequences confirmed the position of strain MSL-04T in the genus Microbacterium and showed that it belonged to the same clade as Microbacterium ulmi but was distinct from its nearest neighbours. The 16S rRNA gene sequence of strain MSL-04T showed the highest levels of similarity with respect to Microbacterium ulmi LMG 20991T (97.5% similarity) and Microbacterium arborescens IFO 3750T (97 %). The G+C content of the DNA was 71.0 mol%. The DNA-DNA relatedness between MSL-04T and its closest neighbours (≤70 %) showed that the strain represents a distinct genomic species. On the basis of the phenotypic and genotypic results, strain MSL-04T represents a novel species in the genus Microbacterium, for which the name Microbacterium kribbense sp. nov. is proposed. The type strain is MSL-04T (=KCTC 19269T = 5DSM 19265T).