Microvirga terrestris sp. nov., and Microvirga arvi sp. nov., isolated from soil in South Korea.

Two novel Gram-stain-negative, aerobic, rod shaped bacterial strains BT290 and BT689 were isolated from soil collected in South Korea. Colony morphologies of both strains were circular and convex while the colors of BT290 and BT689 were light-pink and white, respectively. Phylogenetic analysis based on 16S rRNA gene sequences revealed that BT290 and BT689 belong to a distinct lineage within the genus Microvirga (family Methylobacteriaceae, order Rhizobiales, class Alphaproteobacteria, phylum Proteobacteria, kingdom Bacteria). The 16S rR NA gene sequence similarity between two strains was 97.9%. Both strains had the similar quinone system, with ubiquinone 10 (Q-10) as the major respiratory quinone. The major polar lipids of strains BT290 and BT689 were phosphatidylethanolamine (PE), diphosphatidylglycerol (DPG), phosphatidylcholine (PC), and phosphatidylglycerol (PG). The major cellular fatty acids of strain BT290 were C ω7c (58.2%) and C (17.7%), while those of strain BT689 were C ω7c (61.8%) and C (10.8%). On the bases of polyphasic analysis (phylogenetic, chemotaxonomic, and biochemical), strains BT290 and BT689 can be suggested as novel bacterial species within the genus Microvirga and the proposed names are Microvirga terrestris and Microvirga arvi, respectively. The type strain of Microvirga terrestris is BT290 (= KCTC 72367 = NBRC 114844) and the type strain of Microvirga arvi is BT689 (= KACC 22016 = NBRC 114858), respectively.