Methylibium fulvum sp nov., a member of the Betaproteobacteria isolated from ginseng field soil, and emended description of the genus Methylibium

Abstract

Two bacterial strains, designated Gsoil 322 T and Gsoil 328, were isolated from soil of a ginseng field in Pocheon province (Republic of Korea). The strains were Gram-negative, motile, aerobic rods that showed nearly identical physiological profiles and similar chemotaxonomic profiles. The two strains were oxidase-positive but catalase-negative, reduced nitrate to nitrite and had fatty acid profiles in which C-16:0, C-17:0 cyclo and C-16:10 omega 7c/iso-C-15:0 2-OH were predominant. The DNA G + C contents of Gsoil 322(T) and Gsoil 328 were 66.6 and 66.7 mol%, respectively. Q-8 was observed as the major quinone. Comparative 16S rRNA gene sequence analysis showed that strain Gsoil 322 T belongs to the class Betaproteobacteria and was most closely related to Methylibium petroleiphilum ATCC BAA-1232(T) (97.5% sequence similarity). On the basis of its phenotypic properties and phylogenetic distinctiveness, strain Gsoil 322(T) (=KCTC 12591(T) =LMG 23394(T)) was classified in the genus Methylibium as the type strain of a novel species, for which the name Methylibium fulvum sp. nov. is proposed.