Tenacibaculum aquimarinum sp. nov., isolated from a marine alga and seawater

Abstract

Two Gram-stain-negative, aerobic and yellow-pigmented bacterial strains, designated K20-16T and MSW2, were isolated from a marine red alga (Chondrus species) and seawater, respectively. Both strains were oxidase-positive, weakly catalase-positive and non-flagellated rods with gliding motility. Menaquinone-6 was detected as the sole isoprenoid quinone in both strains. Iso-C15:0, iso-C15:0 3-OH, iso-C15:1 G, C15:1 ω6c and summed feature 3 (comprising C16:1 ω7c and/or C16:1 ω6c) were identified in both strains as major fatty acids. Phosphatidylethanolamine was not identified in strain K20-16T, but it was identified in strain MSW2. The genomic DNA G+C contents of strains K20-16T and MSW2 were 30.5 and 30.7 %, respectively. Strains K20-16T and MSW2 shared 99.7% 16S rRNA gene sequence similarity, 97.7% average nucleotide identity (ANI), and 80.5% digital DNA–DNA hybridization (DDH) value, indicating that they are the same species. Phylogenetic analyses based on 16S rRNA gene and 92 concatenated core protein sequences revealed that strains K20-16T and MSW2 formed a phylogenic lineage within the genus Tenacibaculum and were most closely related to Tenacibaculum todarodis LPB0136T with 98.3 and 98.0% 16S rRNA gene sequence similarities, respectively. ANI and digital DDH values between strains K20-16T and MSW2 and other type strains were less than 91.4 and 43.1 %, respectively. Based on the phenotypic, chemotaxonomic and molecular features, strains K20-16T and MSW2 represent a novel species of the genus Tenacibaculum, for which the name Tenacibaculum aquimarinum sp. nov. is proposed. The type strain is K20-16T (=KACC 22 342T=JCM 35 023T). © 2022 The Authors.