THE METABOLISM OF FLUORANTHENE BY A SPECIES OF MYCOBACTERIUM

A Mycobacterium sp., which was previously isolated from oil-contaminated estuarine sediments, mineralized the polycyclic aromatic hydrocarbon fluoranthene. When supplemented with an alternative carbon source, the organism was able to mineralize up to 78% of the added [3-C-14]fluoranthene to C-14O2 after 5 days of incubation, with relatively little accumulation of intermediate metabolites. The distribution of the C-14 label was monitored throughout the mineralization process. The Mycobacterium degraded in excess of 95% fluoranthene within a 24 hour period following an initial 6-12 h lag phase. At that point approximately 53% of the radioactivity was located in the ethyl acetate extractable fraction, 31.8% in CO2, and 14.7% in the aqueous phase. Incubation of the Mycobacterium sp. with soil and river water, in the presence of fluoranthene, enhanced mineralization of fluoranthene by 92.7% over the indigenous biota. These results, in conjunction with previously reported studies, suggest the potential application of this Mycobacterium sp. for the bioremediation of polycyclic aromatic hydrocarbon contaminated wastes in the environment.