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 : 1)omega7c/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.