Mucilaginibacter aquatilis sp. nov., Mucilaginibacter arboris sp. nov., and Mucilaginibacter ginkgonis sp. nov., novel bacteria isolated from freshwater and tree bark.

Abstract

Three Gram-stain-negative, strictly aerobic, non-motile and rod-shaped bacterial strains, designated as HME9299T, HMF7410T and HMF7856T, were isolated from freshwater and tree bark collected in Yong-in, Republic of Korea. Strains HME9299T, HMF7410T and HMF7856T exhibited the highest 16S rRNA gene sequence similarities of 97.2, 94.4 and 96.4 % to Mucilaginibacter daejeonensis Jip 10T, Mucilaginibacter terrae CCM 8645T and Mucilaginibacter phyllosphaerae PP-F2F-G21T, respectively. Among themselves, the values were 94.1-95.7 %. Phylogenetic analysis of the 16S rRNA gene sequences of the three isolates revealed that they belonged to the genus Mucilaginibacter within the family Sphingobacteriaceae. The predominant fatty acids of three strains were summed feature 3 (comprising C16 : 1 ω7c and/or C16 : 1 ω6c) and iso-C15 : 0. Strain HME9299T contained a relatively large amount of C16 : 1 ω5c. The predominant respiratory quinone was menaquinone-7. The genome sizes of strains HME9299T, HMF7410T and HMF7856T were 4.33, 4.16 and 3.68 Mbp, respectively, and their DNA G+C contents were 41.6, 38.4 and 43.9 mol%, respectively. Based on the results of the phenotypic, genotypic, chemotaxonomic and phylogenetic investigation, three novel species, Mucilaginibacter aquatilis sp. nov, Mucilaginibacter arboris sp. nov. and Mucilaginibacter ginkgonis sp. nov., are proposed. The type strains are HME9299T (=KCTC 42122T=DSM 29146T), HMF7410T (=KCTC 62464T=NBRC 113227T) and HMF7856T (=KCTC 72782T=NBRC 114275T), respectively.