Novosphingobium ovatum sp. nov., isolated from a freshwater mesocosm.

A bacterial strain, designated FSY-8 ^T , was isolated from a freshwater mesocosm in Taiwan and characterized using the polyphasic taxonomy approach. Cells of strain FSY-8 ^T were aerobic, Gram-stain-negative, rod-shaped, non-motile and formed yellow coloured colonies on Reasoner's 2A agar. Growth occurred at 20-40 °C (optimum, 30-37 °C) and pH 5-7 (optimum, pH 6) and in the presence of 0-0.5 % NaCl (optimum, 0 %, w/v). The major fatty acids (>10 %) of strain FSY-8 ^T were summed feature 8 (C _18 : 1  ω 7 c and/or C _18 : 1  ω 6 c ) and summed feature 3 (C _16 : 1  ω 7 c and/or C _16 : 1  ω 6 c ). The polar lipid profile consisted of a mixture of phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine, phosphatidylmonomethylethanolamine, phosphatidyldimethylethanolamine, sphingoglycolipid, diphosphatidylglycerol, an uncharacterized aminophospholipid, an uncharacterized glycolipid and an uncharacterized lipid. The major polyamine was spermidine. The major isoprenoid quinone was Q-10. The DNA G+C content was 64.8 mol %. Phylogenetic analyses based on 16S rRNA gene sequences and coding sequences of 92 protein clusters indicated that strain FSY-8 ^T formed a phylogenetic lineage in the genus Novosphingobium . Strain FSY-8 ^T showed 71.6-77.2 % average nucleotide identity and 19.9-22.8 % digital DNA-DNA hybridization identity with the strains of other Novosphingobium species. On the basis of phenotypic and genotypic properties and phylogenetic inference, strain FSY-8 ^T should be classified in a novel species of the genus Novosphingobium , for which the name Novosphingobium ovatum sp. nov. is proposed. The type strain is FSY-8 ^T (=BCRC 81051 ^T =LMG 30053 ^T =KCTC 52812 ^T ).