Characterization of a bacterium and its pentachlorophenol-degrading enzymes

The objectives of this research were to determine the optimum pentachlorophenol concentration, temperature, and pH for the growth of the strain of bacterium that was isolated from a land farm in Joplin, Missouri and to determine if the bacterium degrades pentachlorophenol via a particular monoxygenase pathway. Over the past ten years, this bacterium has been continuously cultivated at the Mississippi State University Forest Products Laboratory for commercial purposes. Because several genera of bacteria that degrade PCP have been reclassified, fatty acids analyses and 16S rRNA analyses were used to determine the identification of the bacterium. Gas chromatography of the cellular fatty acids identified the bacterium as Pseudomonas aeruginosa. The 16S rRNA analysis also identified the bacterium as Pseudomonas aeruginosa. Three studies were conducted to determine the optimum pentachlorophenol concentration, temperature, and pH at which the bacterium would grow exponentially without substantial growth inhibition. The optimum PCP concentration for this strain of bacterium was 40 PPM PCP, optimum temperature was 35°C, and optimum pH of 7.0. General Polymerase Chain Reaction protocols were used to try to amplify the DNA corresponding to the third enzyme in the PCP-4-monooxygenase degradation pathway. Unfortunately, amplification did not occur with either our bacterium or a know ATCC culture.