Biodegradation of 1-nitropyrene.
The metabolism of 14C-labeled 1-nitropyrene in microcosms containing nonsterile estuarine sediments, and in cultures of a Mycobacterium sp. previously isolated from oil-contaminated sediments was investigated. Although mineralization of 1-nitropyrene by pure cultures of the Mycobacterium sp. totaled only 12.3% after 10 days of incubation, over 80% of the ethyl acetate extractable 14C-labeled compounds consisted of 1-nitropyrene metabolites. High pressure liquid chromatographic analysis of 1-nitropyrene degradation products indicated that two major metabolites were formed. They were identified as 1-nitropyrene cis-9,10- and 4,5-dihydrodiols, based on their UV-visible, mass and NMR spectra. Time course studies in microcosms showed that 1-nitropyrene was degraded slowly under aerobic and anaerobic conditions in estuarine sediments. Less than 1% had been converted to 14CO2 after 8 weeks of aerobic incubation. The addition of 1-nitropyrene to anaerobic sediments resulted in no 14CO2 evolution; however, the nitro group of 1-nitropyrene was reduced to form 1-aminopyrene. Although the mineralization of 1-nitropyrene in sediments was slow, the Mycobacterium sp. metabolized 1-nitropyrene in pure culture. This bacterium appears promising for the bioremediation of this ubiquitous pollutant in contaminated waste.
Heitkamp
M A
MA
National Center for Toxicological Research, Food and Drug Administration, Jefferson, AR 72079.
Freeman
J P
JP
Miller
D W
DW
Cerniglia
C E
CE
D000332:Aerobiosis; D000693:Anaerobiosis; D001673:Biodegradation, Environmental; D002851:Chromatography, High Pressure Liquid; D004787:Environmental Pollution / Q000517:prevention & control*; D007700:Kinetics; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D009161:Mycobacterium / Q000378:metabolism*; D011721:Pyrenes / Q000378:metabolism*; D012988:Soil Microbiology; D013056:Spectrophotometry, Ultraviolet; D014871:Water Microbiology
D011721:Pyrenes; C032668:1-nitropyrene