title: Biotransformation of 2,4,6-trinitrotoluene (TNT) by the fungus Fusarium oxysporum.
abstract: The fungus Fusarium oxysporum was isolated and identified from the aquatic plant M. aquaticum. The capability of this fungus to transform 2,4,6-trinitrotoluene (TNT) in liquid cultures was investigated TNT was added to shake flask cultures and transformed into 2-amino-4,6-dinitrotoluene (2-A-DNT), 4-amino-2,6-dinitrotoluene (4-A-DNT), and 2,4-diamino-6-nitrotoluene (2,4-DAT) via 2- and 4-hydroxylamino-dinitrotoluene derivatives, which could be detected as intermediate metabolites. Transformation of TNT, 2-A-DNT, and 4-A-DNT was observed by whole cultures and with isolated mycelium. Cell-free protein extracts from the extracellular, soluble, and membrane-bound fractions were prepared from this fungus and tested for TNT-reducing activity. The concentrated extracellular culture medium was unable to transform TNT; however, low levels of TNT transformation were observed by the membrane fraction in the presence of nicotinamide adenine dinucleotide phosphate in an argon atmosphere. A concentrated extract of soluble enzymes also transformed TNT, but to a lesser extent. When TNT toxicity was studied with this fungus, a 50% decrease in the growth of F. oxysporum mycelium was observed when exposed to 20 mg/L TNT.
authors.affiliation: Department of Biochemistry and Molecular Biology, Center for Biological Resource Recovery, University of Georgia, Athens, Georgia, USA. choehamer@yahoo.com
authors.forename: Christopher F
authors.initials: CF
authors.lastname: Hoehamer
authors.forename: N Lee
authors.initials: NL
authors.lastname: Wolfe
authors.forename: Karl Erik L
authors.initials: KE
authors.lastname: Eriksson
mesh_terms: D000814:Aniline Compounds / Q000378:metabolism; D001711:Biotransformation; D003470:Culture Media; D046508:Culture Techniques; D005670:Fusarium / Q000254:growth & development / Q000302:isolation & purification / Q000378:metabolism*; D025282:Mycelium / Q000378:metabolism; D014052:Toluidines / Q000378:metabolism; D014303:Trinitrotoluene / Q000378:metabolism*
chemical_list: D000814:Aniline Compounds; D003470:Culture Media; D014052:Toluidines; D014303:Trinitrotoluene; C035208:2-amino-4,6-dinitrotoluene; C035207:4-amino-2,6-dinitrotoluene; C046358:2,4-diamino-6-nitrotoluene