Isolation and Characterization of a Novel Bisphenol A-degrading Bacterium Pseudomonas paucimobilis Strain FJ-4.

Abstract

From the activated sludge treating the wastewater of an epoxy resin manufacturing plant, abisphenol A (BPA) -degrading bacterial strain FJ-4 which can grow on BPA as the sole carbon and energy source was isolated. It was an aerobic, gram-negative and rod-shaped baterium, and identified as Pseudomonas paucimobilis. Strain FJ-4 could efficiently degrade BPA up to 1.0 mM. However, approximately 15%of total organic carbon (TOC) remained in the medium even when BPA was completely removed, suggesting the accumulation of a refractory metabolic intermediate (s) . At the saturated concentration of BPA (ca.1.5 mM), the growth of and BPA degradation by strain FJ-4 were not observed. The specific BPA-degrading activity of BPA-grown cells was about three times higher than that of glucose-grown cells, indicating that the BPA-degrading enzyme (s) in FJ-4 is inducible. The optimal temperature and pH for BPA degradation were 30°C and 7.0, respectively. Specific BPA-degrading activity of FJ-4 was roughly described by the Michaelis-Menten kinetics although a slight decrease in the activity was observed at BPA concentration more than 0.5 mM. Strain FJ-4 could utilize a limited range of aromatic compounds, and catabolic pathways for only benzoic acid and p-hydroxybenzoic acid (or p-hydroxyacetophenone) were found. Strain FJ-4 also showed a strict catabolic range for other bisphenols and bisphenol-like compounds.