Microbacterium excoecariae sp. nov., a novel endophytic actinobacterium isolated from bark of Excoecaria agallocha Linn.

ABSTRACT

A Gram-stain-positive, aerobic actinobacterium, designated strain CBS5P-1T, was isolated from bark of Excoecaria agallocha Linn collected from Guangxi Zhuang Autonomous Region, PR China. Cells were short rods. Colonies were light yellow, circular and had entire margins. Strain CBS5P-1T grew at 10-37 °C (optimum, 30 °C) and pH 6.0-12.0 (optimum, pH 7.0-8.0). Its nearest phylogenetic neighbour was Microbacterium amylolyticum DSM 24221T with 97.1 % 16S rRNA gene sequence similarity. The genomic DNA G+C content of strain CBS5P-1T was 71.8 mol%. Anteiso-C15   0, anteiso-C17  0, iso-C16  0 and C160 were predominant cellular fatty acids. Major menaquinones were MK-11 and MK-10. The polar lipids consisted of diphosphatidylglycerol, phosphatidylglycerol, an unidentified glycolipid and an unidentified phospholipid. The combination of chemotaxonomic, phylogenetic and phenotypic data clearly distinguished strain CBS5P-1T from its phylogenetic neighbour. Accordingly, the name Microbacterium excoecariae sp. nov. is proposed to accommodate this new member of the genus Microbacterium. The type strain is CBS5P-1T (=KCTC 49239T=CGMCC 1.13862T).