Burkholderia oxyphila sp. nov., a bacterium isolated from acidic forest soil that catabolizes (+)-catechin and its putative aromatic derivatives

Abstract

A novel bacterium, designated strain OX-01T, was isolated from acidic soil, taxonomically investigated and identified as an agent that catabolizes (+)-catechin into taxifolin. Strain OX-01T is a Gram-reaction-negative, aerobic, non-sporulating, non-motile and rod-shaped bacterium. 16S rRNA gene sequence analysis identified this strain as a member of the genus Burkholderia and occupying a phylogenetic position closest to, but clearly distinct from, Burkholderia sacchari. Strain OX-01T does not have any nif genes, which are required for N2-fixation, in its genome, a feature that is similar to B. sacchari, which lacks nifH, but is distinct from the N2-fixing features of many other phylogenetically related taxa, such as Burkholderia ferrariae, B. heleia, B. mimosarum, B. nodosa, B. silvatlantica, B. tropica and B. unamae. Strain OX-01T has the following chemotaxonomic characteristics: the major ubiquinone is Q-8, the DNA G+C content is 64 mol% and the major fatty acids are C16 : 0, C17 : 0 cyclo and C18 : 1 ω7c. It also has a unique profile of carbohydrate utilization among other species of the genus Burkholderia. The strain cannot assimilate many pentoses, hexoses and oligosaccharides, whereas it can catabolize (+)-catechin and its putative aromatic derivatives, such as 4-hydroxy-3-methoxycinnamic acid, protocatechuic acid, p-hydroxybenzoic acid, trans-p-coumaric acid and vanillic acid. Based on its morphological, physiological and chemotaxonomic characteristics, together with DNA–DNA relatedness values and 16S rRNA gene sequence comparison data, we show that strain OX-O1T represents a novel species of the genus Burkholderia, for which the name Burkholderia oxyphila sp. nov. is proposed. The type strain is OX-01T (=NBRC 105797T =DSM 22550T).