Flavihumibacter profundi sp nov., isolated from eutrophic freshwater sediment

A Gram-stain-positive, aerobic, non-motile, non-spore-forming, and rod-shaped bacterium, designated strain CHu64-6-1(T), was isolated from a 67-cm-long sediment core collected from the Daechung Reservoir at a water depth of 17-m in Daejeon, Republic of Korea. Comparative 16S rRNA gene sequence studies placed the new isolate in the class Sphingobacteriia, and the isolate is notably most closely related to Flavihumibacter sediminis CJ663(T) (98.1% similarity), Flavihumibacter solisilvae 3-3(T) (97.8%), Flavihumibacter petaseus T41(T) (97.5%), Flavihumibacter cheonanensis WS16(T) (97.4%), and Flavihumibacter stibioxidans YS-17(T) (97.2%). The cells of strain CHu64-6-1(T) formed yellow colonies on R2A agar and contained MK-7 as the only menaquinone, phosphatidylethanolamine, an unidentified phospholipid, and two unidentified aminolipids as the major polar lipids, and C-15:0 iso, C-17:0 iso 3-OH, C-15:1 iso G, and C-16:1 omega 5c as the major fatty acids (> 5%). The DNA G + C content of the genome was determined to be 46.5 mol%. The DNA-DNA hybridization values of strain CHu64-6-1(T) with F. sediminis CJ663(T), F. solisilvae 3-3(T), F. petaseus T41(T), F. cheonanensis WS16(T), and F. stibioxidans YS-17(T) were 12.4-33.2%. Based on the combined genotypic and phenotypic data, we propose that strain CHu64-6-1(T) represents a novel species of the genus Flavihumibacter, for which the name Flavihumibacter profundi sp. nov. is proposed. The type strain is CHu64-6-1(T) (= KCTC 62290(T) = CCTCC AB 2018060(T)).