Sphingobacterium oryzagri sp. nov., isolated from rice paddy soil

An aerobic, Gram-stain-negative and short rod-shaped bacterial strain, designated M6-31^T, was isolated from rice paddy soil sampled in Miryang, Republic of Korea. Growth was observed at 4-35 °C (optimum, 28 °C), pH 6.0-9.0 (optimum, pH 7.0-8.0) and in the presence of 0-4 % (w/v) NaCl (optimum, 0 % w/v). Phylogenetic analysis based on 16S rRNA gene sequences grouped strain M6-31^T with Sphingobacterium bambusae IBFC2009^T, Sphingobacterium griseoflavum SCU-B140^T and Sphingobacterium solani MLS-26-JM13-11^T in the same clade, with the 16S rRNA gene sequence similarities ranging from 95.8 to 96.6 %. A genome-based phylogenetic tree reconstructed by using all publicly available Sphingobacterium genomes placed strain M6-31^T with S. bambusae KACC 22910^T, 'Sphingobacterium deserti' ACCC 05744^T, S. griseoflavum CGMCC 1.12966^T and Sphingobacterium paludis CGMCC 1.12801^T. Orthologous average nucleotide identity and digital DNA-DNA hybridization values between strain M6-31^T and its closely related strains were lower than 74.6 and 22.0 %, respectively. The respiratory quinone was menaquinone-7, and the major polar lipid was phosphatidylethanolamine. The major fatty acids (>10 %) were C_15 : 0 iso, C_17 : 0 iso 3OH and summed feature 3. The phenotypic, chemotaxonomic and genotypic data obtained in this study showed that strain M6-31^T represents a novel species of the genus Sphingobacterium, for which the name Sphingobacterium oryzagri sp. nov. (type strain M6-31^T=KACC 22765^T=JCM 35893^T) is proposed.