Aquirufa rosea sp. nov., isolated from a freshwater lake

A bacterial strain designated CAR-16^T was isolated from a freshwater lake in Taiwan and characterized using the polyphasic taxonomic approach. Cells were Gram-stain-negative, aerobic, motile by gliding, rod-shaped and formed rose-colored colonies. Optimal growth occurred at 30 °C, pH 7 and with 0 % NaCl. Phylogenetic analyses based on 16S rRNA gene sequences and coding sequences of 92 protein clusters indicated that CAR-16^T represented a member of the family Cytophagaceae and formed a phylogenetic lineage in the genus Aquirufa. CAR-16^T was most closely related to Aquirufa nivalisilvae 59G-WUEMPEL^T with a 99.7 % 16S rRNA gene sequence similarity. CAR-16^T showed 71.2-79.5 % average nucleotide identity and 17.8-21.7 % digital DNA-DNA hybridization identity with the strains of other species of the genus Aquirufa. The major fatty acids of strain CAR-16^T were iso-C_15 : 0, iso-C_15 : 0 3-OH, C_16 : 1ω5c and summed feature 3 (C_16 : 1ω7c/C_16 : 1ω6c and/or iso-C_15 : 0 2-OH). The polar lipid profile consisted of a mixture of phosphatidylethanolamine and several uncharacterized aminophospholipids, phospholipids and lipids. The major isoprenoid quinone was MK-7. The genomic DNA G+C content of CAR-16^T was 38.8 mol%. On the basis of phenotypic and genotypic properties and phylogenetic inference, CAR-16^T should be classified as representing a novel species of the genus Aquirufa, for which the name Aquirufa rosea sp. nov. is proposed. The type strain is CAR-16^T (=BCRC 81153^T=LMG 30923^T=KCTC 62869^T).