Isolation and characterization of organisms that can degrade xenobiotics could help in developing microbial strains that could attack persistent pollutants more aggressively. Since the genes encoding catabolic pathways are often clustered and plasmid borne (Chaudhry and Chapalamuguda, 1991), these clusters can be cloned and if they are readily expressed in the new host, then microorganisms with a broader substrate spectrum can be developed.