A Gram-negative, nonmotile and rod-shaped bacterial strain was isolated from the rhizosphere of Platycodon grandiflorum in a study of bacterial diversity, and its taxonomic position was investigated by a genotypic and phenotypic analysis. This isolate, designated as DR-f4, grew at 4-30 degrees C (optimally at 20-25 degrees C) and in the presence of 0-1% (w/v) NaCl. It contained MK-7 as the predominant menaquinone. The isolate had activities of catalase, oxidase and beta-galactosidase and hydrolyzed aesculin, casein, carboxymethyl-cellulose, starch and L-tyrosine. The major cellular fatty acids were summed feature 3 (C(16:1)omega7c and/or iso-C(15:0) 2OH) and iso-C(15:0). The DNA G+C content was 42.6 mol%. This isolate belonged to the genus Mucilaginibacter based on phylogenetic analysis using 16S rRNA gene sequences. The nearest phylogenetic neighbors of strain DR-f4(T) were Mucilaginibacter lappiensis ANJL12(T) and Mucilaginibacter rigui WPCB133(T), with 16S rRNA gene sequence similarity levels of 96.9% and 96.4%, respectively. The genotypic and phenotypic evidence suggests that strain DR-f4(T) should be classified as a novel species, for which the name Mucilaginibacter dorajii sp. nov. is proposed. The type strain for the novel species is DR-f4(T) (=KACC 14556(T)=JCM 16601(T)).