<i>Poseidonibacter ostreae</i> sp. nov., Isolated from the Gut of <i>Ostrea</i> from the Seomjin River

Abstract

Three Gram-negative strains, SJOD-M-6T, SJOD-M-5, and SJOD-M-33, were isolated from Ostrea denselamellosa. These strains are oxidase- and catalase-positive coccoids that thrive aerobically. The three strains shared 100.0% 16S rRNA gene sequence similarity and showed average nucleotide identity (ANI) and digital DNA–DNA hybridization (dDDH) values of 99.7–99.8% and 93.8–96.8%, suggesting that they belonged to the same species. Phylogenetic analysis based on the 16S rRNA gene revealed that all three isolates belong to the genus Poseidonibacter. Their closest neighbors were Poseidonibacter parvus LPB0137T (98.8%), Poseidonibacter antarcticus SM1702T (98.7%), and Poseidonibacter lekithochrous LFT 1.7T (95.5%). However, the ANI and dDDH values between SJOD-M-6T (the representative strain of the novel species) and its closest phylogenetic relatives fell well below the established cut-off values of T, SJOD-M-5, and SJOD-M-33 are classified as novel species within the genus Poseidonibacter. We propose the name Poseidonibacter ostreae sp. nov. for this novel species, with the type strain being SJOD-M-6T (=KCTC 72758T = NBRC 114334T = FBCC-B685).

Keywords

• <i>Poseidonibacter ostreae</i>
• <i>Ostrea denselamellosa</i>
• new taxa