Novosphingobium bradum sp. nov., isolated from a spring.

Abstract

A bacterial strain designated STM-24T was isolated from a spring in Taiwan and characterized using the polyphasic taxonomic approach. Cells of strain STM-24T were Gram-staining- negative, aerobic, poly-β-hydroxybutyrate accumulating, non-motile, rod shaped and forming light yellow-coloured colonies. Growth occurred at 15-30 °C (optimum, 20 °C), at pH 5.0-9.0 (optimum, pH 6.0) and with 0-0.5 % NaCl (optimum, 0 %). Phylogenetic analyses based on 16S rRNA gene sequences showed that strain STM-24T belonged to the genus Novosphingobium and was most closely related to Novosphingobium piscinae SLH-16T with sequence similarity of 98.4 %. The major fatty acids (>10 %) of strain STM-24T were C18 : 1ω7c, summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c) and C16 : 0. The major 2-hydroxy fatty acid was C14 : 0 2-OH. The polar lipid profile consisted of phosphatidylglycerol, phosphatidylethanolamine, phosphatidylmonomethylethanolamine, phosphatidyldimethylethanolamine, sphingoglycolipid, phosphatidylcholine and several uncharacterized lipids. The major polyamine was spermidine. The major isoprenoid quinone was Q-10. The DNA G+C content was 69.1mol%. The DNA-DNA hybridization value for strain STM-24T with N.piscinae SLH-16T, Novosphingobium taihuense JCM 12465T and Novosphingobium subterraneum DSM 12447T was less than 55 %. Phenotypic characteristics of the novel strain also differed from those of the closest related species of the genus Novosphingobium. On the basis of the genotypic, chemotaxonomic and phenotypic data, strain STM-24T represents a novel species in the genus Novosphingobium, for which the name Novosphingobium bradum sp. nov. is proposed. The type strain is STM-24T (=BCRC 80925T=LMG 29291T=KCTC 42984T).