Flavobacterium stagni sp. nov., isolated from a freshwater reservoir

Strain WWJ-16 T was isolated from a freshwater reservoir in Taiwan. Phylogenetic analyses based on 16S rRNA gene sequences and an up-to-date bacterial core gene set (92 protein clusters) indicated that strain WWJ-16 T is affiliated with the species in the genus Flavobacterium. Strain WWJ-16 T was most closely related to Flavobacterium fontis MIC3010 T (97.9 % 16S rRNA gene sequence identity) and Flavobacterium squillarum CMJ-5 T (97.6 %). Strain WWJ-16 T showed 77.4 % average nucleotide identity and 20.6 % digital DNA-DNA hybridization identity with F. fontis MIC3010 T . Cells of strain WWJ-16 T were Gram-stain-negative, strictly aerobic, non-motile, rod-shaped and formed yellow colonies. Optimal growth occurred at 25 °C, pH 7 and in 0.5-1 % NaCl (w/v). Strain WWJ-16 T contained iso-C15 : 1 G and iso-C15 : 0 as predominant fatty acids. The major hydroxyl fatty acids were iso-C15 : 0 3-OH, iso-C17 : 0 3-OH and iso-C16 : 0 3-OH. The polar lipid profile consisted of phosphatidylethanolamine, four uncharacterized aminophospholipids and four uncharacterized phospholipids. The major polyamine was homospermidine. The major isoprenoid quinone was MK-6. The genomic DNA G+C content of strain WWJ-16 T was 39.4 mol%, as determined by genome sequencing. The genotypic and phenotypic characteristics indicate that strain WWJ-16 T represents a novel species of the genus Flavobacterium, for which the name Flavobacterium stagni sp. nov. is proposed. The type strain is WWJ-16 T (=BCRC 81125 T =LMG 30600 T =KCTC 62515 T ).