Abstract

A Gram-stain-negative, non-motile, non-spore-forming, rodshaped, aerobic bacterial strain, designated S1-2-2-5T, was isolated from the Jeollabuk-do province, Republic of Korea, and was characterized taxonomically using a polyphasic approach. Comparative 16S rRNA gene sequence analysis showed that strain S1-2-2-5T belonged to the family Cytophagaceae in phylum Bacteroidetes, and was most closely related to Hymenobacter terrae DG7AT (98.2%), Hymenobacter rubidus DG7BT (98.0%), Hymenobacter soli PB17T (97.7%), Hymenobacter daeguensis 16F3Y-2T (97.2%) and Hymenobacter saemangeumensis GSR0100T (97.0%). The G + C content of the genomic DNA of strain S1-2-2-5T was 59.4 mol%. The detection of menaquinone MK-7 as the predominant respiratory quinone, a fatty acid profile with summed feature 3 (C16:1 ω7c/C16:1 ω6c; 32.0%), C15:0 iso (19.0%), and C15:0 anteiso (15.0%) as the major components, and a polar lipid profile with phosphatidylethanolamine as the major component supported the affiliation of strain S1-2-2-5T to the genus Hymenobacter. The DNA-DNA relatedness between strain S1-2-2-5T and H. terrae KCTC 32554T, H. rubidus KCTC 32553T, H. soli KCTC 12607T, H. daeguensis KCTC 52537T, and H. saemangeumensis KACC 16452T were 49.5, 48.2, 34.1, 28.1, and 31.8% respectively, clearly showing that the isolate is not related to them at the species level. Strain S1-2-2-5T could be clearly differentiated from its closest neighbors on the basis of its phenotypic, genotypic and chemotaxonomic features. Therefore, strain S1-2-2-5T represents a novel species of the genus Hymenobacter, for which the name Hymenobacter terrigena sp. nov. is proposed. The type strain is S1-2-2-5T (= KCTC 52737T = JCM 32195T).

• Keywords: Hymenobacter; Bacteroidetes; polyphasic taxonomy