Isolation and characterization of a pentachlorophenol-degrading bacterium.

With a new enrichment protocol, pentachlorophenol (PCP)-degrading bacteria were isolated from soil, water, and sewage. When characterized, all isolates were related and shared characteristics of the genus Arthrobacter. Growth rates for strain NC were determined for a number of substrates, including PCP and 2,4,6-trichlorophenol. Changes in PCP concentration affected growth rate and length of the lag phase but not cell yield. Increasing the pH from 6.8 to 7.8 decreased the length of the lag phase for growth on PCP. Cessation of growth, upon incremental addition of PCP, was found to be related to a decrease in pH rather than to a buildup of a toxic metabolite. Degradation of PCP by strain NC was shown to be complete.