Microvirga pudoricolor sp. nov., and Microvirga alba sp. nov., isolated from soil in South Korea.

Abstract

Two novel Gram-stain-negative, aerobic, rod-shaped, circular, convex, light-pink and white-colored bacterial strains BT291T and BT350T were isolated from soil collected in Uijeongbu city (37° 44' 55″ N, 127° 2' 20″ E) and Jeju island (33° 22' 48″ N, 126° 31' 48″ E), respectively, South Korea. Phylogenetic analysis based on 16S rRNA gene sequences revealed that each of the strains BT291T and BT350T belong to a distinct lineages within the genus Microvirga (family Methylobacteriaceae, order Rhizobiales, class Alpha Proteobacteria, phylum Proteobacteria, kingdom Bacteria). The 16S rRNA gene sequence similarity between the two strains BT291T and BT350T was 97.4%. The two strains were found to have the same quinone system, with Q-10 as the major respiratory quinone. The major polar lipids of strains BT291T and BT350T were phosphatidylethanolamine (PE), diphosphatydilglycerol (DPG), phosphatidylcholine (PC) and phosphatidylglycerol (PG). The major cellular fatty acids of strain BT291T were C18:1 ω7c (58.2%) and cyclo-C19:0 ω8c (25.7%). The major cellular fatty acids of strain BT350T were C18:1 ω7c (38.5%) and cyclo-C19:0 ω8c (27.7%). Based on the polyphasic analysis (phylogenetic, chemotaxonomic and biochemical), strains BT291T and BT350T can be suggested as two novel bacterial species within the genus Microvirga and the proposed names are Microvirga pudoricolor and Microvirga alba, respectively. The type strain of Microvirga pudoricolor is BT291T (= KCTC 72368T = NBRC 114845T) and the type strain of Microvirga alba is BT350T (= KCTC 72385T = NBRC 114848T).