Microlunatus elymi sp. nov., a novel actinobacterium isolated from rhizospheric soil of the wild plant Elymus tsukushiensis

An actinobacterial strain, designated KUDC0627^T, was isolated from rhizospheric soil that contained Elymus tsukushiensis on the Dokdo Islands, Republic of Korea. Cells were Gram-stain- positive, facultative anaerobic, non-motile and non-endospore- forming cocci. Results of phylogenetic analysis based on 16S rRNA gene sequences indicated that strain KUDC0627^T belongs to the genus Microlunatus and is most closely related to Microlunatus soli DSM 21800^T (98.5 %), Microlunatus endophyticus DSM 100019^T (97.7 %) and Microlunatus ginsengisoli Gsoil 633^T (96.5 %). The average nucleotide identity scores and average amino acid identity values were all below the 95.0 % cut-off point. In silico DNA-DNA hybridization, using the Genome-to- Genome Distance Calculator, estimated that there is 22.3 % DNA relatedness between KUDC0627^T and M. soli DSM 21800^T. The genomic DNA G+C content was 66.9 mol%. The major menaquinone was MK-9(H₄) and the major diagnostic diamino acid in the cell-wall peptidoglycan was ll-diaminopimelic acid. The polar lipid profile included diphosphatidylglycerol, phosphatidylglycerol, unidentified phospholipids, unidentified glycolipids and unidentified lipids. The major cellular fatty acids were iso-C _{15: 0}, anteiso-C _{15: 0} and iso-C _{16: 0}. Based on phenotypic, chemotaxonomic, and phylogenetic data, strain KUDC0627^T (=KCTC 39853^T=JCM 32702^T) represents a novel species, for which the name Microlunatus elymi sp. nov. is proposed.