Ponticoccus alexandrii sp. nov., a novel bacterium isolated from the marine toxigenic dinoflagellate Alexandrium minutum.

During an investigation of the biodiversity of the cultivable bacterial community associated with paralytic shellfish poisoning toxin-producing marine dinoflagellate, Alexandrium minutum a novel algal-associated bacterium, designated strain AT2-AT was isolated. 16S rRNA gene sequence similarity analysis showed that the strain is a member of the genus Ponticoccus, with high sequence similarity to Ponticoccus litoralis DSM 18986T (97.9%) and Ponticoccus lacteus JCM 30379T (96.0%). However, based on the data obtained for the physiological and biochemical characteristics, and low level of DNA-DNA relatedness analysis, the strain could be genotypically and phenotypically differentiated from two type strains of the genus Ponticoccus. Therefore, this algal-associated bacterial strain is concluded to represent a novel species of the genus Ponticoccus, for which the name Ponticoccus alexandrii sp. nov. is proposed. The type strain is AT2-AT (CCTCC AB 2016296T = KCTC 62340T) [corrected].