sp. nov., from phycosphere microbiota of toxic marine dinoflagellate .

A taxonomic study was carried out on a novel algae-associated bacterial strain Z3-1, which was isolated from phycosphere microbiota of toxic marine dinoflagellate 880. Cells of strain Z3-1 were Gram-stain-negative, rod-shaped and strictly aerobic and were motile by means of flagella. Strain Z3-1 grew at 25-42 °C, pH 5.0-10.0 and 1.0-5.0 % (w/v) NaCl. Strain Z3-1 reduced nitrate to nitrite, but did not reduce nitrite to nitrogen gas. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain Z3-1 belongs to the genus showing the highest sequence similarity (97.0 %) to JCM 14935. The average nucleotide identity and digital DNA-DNA hybridization relatedness between strain Z3-1 and type strains of genus with available genome sequences were in the ranges of 72.4-74.4 % and 22.7-23.3 %, respectively. The major fatty acids were summed in feature 8 (C 7c and/or C 6c), C 8c cyclo, C 7c 11-metyl and iso-C. The major polar lipids were determined as diphosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, two unidentified phospholipids and four unidentified polar lipids. The genomic DNA G+C content calculated from genome sequence was 65.6 mol%. Based on genotypic, chemotaxonomic and phenotypic data obtained, strain Z3-1 represents a novel species of the genus , for which the name sp. nov. is proposed with the type strain Z3-1 (=KCTC 62458=CCTCC AB 2017227).