Mucilaginibacter terrigena sp. nov. sp., A Novel Member of the Family Sphingobacteriaceae

Abstract

A bacterial strain, 17JY9-4^T, was isolated from a soil sample collected on Jeju Island, South Korea. Colonies grown on R2A agar are pale pink in color, and cells are Gram-stain negative, short, and rod-shaped. Analysis of 16S rRNA gene sequences identified this strain as a member of the genus Mucilaginibacter in the family Sphingobacteriaceae, with high levels of 16S rRNA sequence similarity shared with Mucilaginibacter lutimaris BR-3^T (98.0%), Mucilaginibacter rigui WPCB133^T (98.0%), Mucilaginibacter phyllosphaerae PP-F2F-G21^T (97.0%), Mucilaginibacter amnicola TAPP7^T (96.8%), and Mucilaginibacter soli R9-65^T (96.7%). Growth of strain 17JY9-4^T occurs at 10-30 °C, pH 6-8, and in the presence of 0-1.0% NaCl. The genomic G+C content is 44.38 mol%. The predominant respiratory quinone of the isolate is MK-7; the major fatty acids are summed feature 3 (C_16:1ω7c/C_16:1ω6c) (39.7%), iso-C_15:0 (22.8%), iso-C_17:0 3-OH (7.8%), and C_16:0 (7.7%); and the major polar lipid is phosphatidylethanolamine. The phenotypic and chemotaxonomic data support the placement of strain 17JY9-4^T within the genus Mucilaginibacter. However, the DNA-DNA relatedness between the isolate and M. rigui, M. lutimaris, M. phyllosphaerae, M. amnicola, and M. soli were 44.3 ± 3.0%, 38.6 ± 3.7%, 23.2 ± 2.9%, 21.9 ± 3.1%, and 18.6 ± 3.7%, 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 17JY9-4^T represents a novel species in the genus Mucilaginibacter, for which the name Mucilaginibacter terrigena sp. nov. is proposed. The type strain is 17JY9-4^T (= KCTC 62294^T = JCM 33049^T).