Isolation and characterization of a new 2,4-dinitrophenol-degrading bacterium Burkholderia sp. strain KU-46 and its degradation pathway.

A gram-negative bacterium, strain KU-46, was isolated from agricultural soil contaminated with pesticides and was found to utilize 2,4-dinitrophenol as the sole source of carbon and nitrogen. Based on 16S rRNA gene sequence analysis and its morphological, biochemical, and physiological characteristics, strain KU-46 was identified as a Burkholderia sp. Metabolite analyses by HPLC and liquid chromatography-MS indicated that 4-nitrophenol, 1,4-benzoquinone, and nitrite are the intermediates of 2,4-dinitrophenol metabolism, and 2,4-dinitrophenol is metabolized via 4-nitrophenol to 1,4-benzoquinone by strain KU-46. The 2,4-dinitrophenol degradation pathway enzymes are induced by both 2,4-dinitrophenol and 4-nitrophenol.