Burkholderia ginsengiterrae sp. nov. and Burkholderia panaciterrae sp. nov., antagonistic bacteria against root rot pathogen Cylindrocarpon destructans, isolated from ginseng soil

Strain DCY85T and DCY85-1T, isolated from rhizosphere of ginseng, were rod-shaped, Gram-reaction-negative, strictly aerobic, catalase positive and oxidase negative. 16S rRNA gene sequence analysis revealed that strain DCY85T as well as DCY85-1T belonged to the genus Burkholderia and were closely related to Burkholderia fungorum KACC 12023T (98.1 and 98.0 % similarity, respectively). The major polar lipids of strain DCY85T and DCY85-1T were phosphatidylethanolamine, one unidentified aminolipid and two unidentified phospholipids. The major fatty acids of both strains are C16:0, C18:1 ω7c and summed feature 3 (C16:1 ω6c and/or C16:1 ω7c). The predominant isoprenoid quinone of each strain DCY85T and DCY85-1T was ubiquinone (Q-8) and the G+C content of their genomic DNA was 66.0 and 59.4 mol%, respectively, which fulfill the characteristic range of the genus Burkholderia. The polyamine content of both DCY85T and DCY85-1T was putrescine. Although both DCY85T and DCY85-1T have highly similar 16S rRNA and identical RecA and gyrB sequences, they show differences in phenotypic and chemotaxonomic characteristics. DNA–DNA hybridization results proved the consideration of both strains as two different species. Based on the results from our polyphasic characterization, strain DCY85T and DCY85-1T are considered novel Burkholderia species for which the name Burkholderia ginsengiterrae sp. nov and Burkholderia panaciterrae sp. nov are, respectively, proposed. An emended description of those strains is also proposed. DCY85T and DCY85-1T showed antagonistic activity against the common root rot pathogen of ginseng, Cylindrocarpon destructans. The proposed type strains are DCY85T (KCTC 42054T = JCM 19888T) and DCY85-1T (KCTC 42055T = JCM 19889T).