Isolation of a novel pentachlorophenol-degrading bacterium, Pseudomonas sp. Bu34.

A pentachlorophenol (PCP)-degrading bacterium was isolated from possible PCP-contaminated soil from Pusan, Korea and identified as a member of the genus Pseudomonas. It used PCP as its sole source of carbon and energy. This micro-organism was capable of degrading PCP more effectively, certified by the increase in cell density and the decrease in PCP substrate. Pseudomonas sp. Bu34 was able to degrade a much higher concentration of PCP (4000 mg l-1) than any previously reported PCP-degrading bacteria and fungi and to grow in mineral salts solution containing one of a variety of chlorophenols. In non-acclimated strain Bu34, the cell number decreased from 87 to 99.9% in 75-4000 mg l-1 PCP at 24 h. In the acclimated strain the PCP toxic effect did not appear with 75 mg l-1 PCP treatment, but 1000-4000 mg l-1 PCP decreased the cell number of strain Bu34 by 25% to 24 h and then the cell number slightly increased at 48 h. Therefore, it suggested that the maximum resistance of acclimated strain Bu34 to PCP was 4000 mg l-1 PCP. We suggest that strain Bu34 could be used as a micro-organism for the bioremediation of highly PCP-contaminated soils, water or wood products.