Methylobacterium segetis sp. nov., a novel member of the family Methylobacteriaceae isolated from soil on Jeju Island.

Abstract

A bacterial strain, 17J42-1T, was isolated from a soil sample collected on Jeju Island, Republic of Korea. Colonies grown on R2A agar were pink in color, and cells were Gram-stain negative, short and rod-shaped. Analysis of 16S rRNA gene sequences identified this strain as a member of the genus Methylobacterium in the family Methylobacteriaceae, with high levels of 16S rRNA sequence similarity shared with Methylobacterium oxalidis 35aT (98.6%), Methylobacterium jeotgali S2R03-9T (97.5%), and Methylobacterium soli YIM 48816T (97.3%). Cells grew at 15-35°C, pH 5-9, and in the presence of 0-1.0% NaCl. The genomic G + C content was 70.2mol% based on the whole genome analysis. The predominant respiratory quinone was ubiquinone Q-10, the major fatty acid was C18:1ω7c (85.3%), and the major polar lipids were phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, and diphosphatidylglycerol. The phenotypic and chemotaxonomic data support the affiliation of strain 17J42-1T with the genus Methylobacterium. However, the DNA-DNA relatedness between the isolate and its closest phylogenetic neighbors was lower than 38%. The OrthoANI and dDDH values between strain 17J42-1T and the closest type strain Methylobacterium oxalidis NBRC 107715T were calculated to be 85.9% and 30.6%, respectively. The results of 16S rRNA gene sequence similarity analysis, DNA-DNA hybridization analysis, and the observed differentiating phenotypic properties from other closely related taxa clearly indicate that strain 17J42-1T represents a novel species in the genus Methylobacterium, for which the name Methylobacterium segetis sp. nov. is proposed. The type strain is 17J42-1T (= KCTC 62267T = JCM 33059T).