title: Nitroalkane oxidase, a carbanion-forming flavoprotein homologous to acyl-CoA dehydrogenase.
abstract: While several flavoproteins will oxidize nitroalkanes in addition to their physiological substrates, nitroalkane oxidase (NAO) is the only one which does not require the anionic nitroalkane. This, in addition to the induction of NAO by nitroethane seen in Fusarium oxysporum, suggests that oxidation of a nitroaliphatic species is the physiological role of the enzyme. Mechanistic studies of the reaction with nitroethane as substrate have established many of the details of the enzymatic reaction. The enzyme is unique in being the only flavoprotein to date for which a carbanion is definitively established as an intermediate in catalysis. Recent structural analyses show that NAO is homologous to the acyl-CoA dehydrogenase and acyl-CoA oxidase families of enzymes. In NAO, the glutamate which acts as the active site base in the latter enzymes is replaced by an aspartate.
authors.affiliation: Department of Biochemistry and Biophysics, Texas A and M University, College Station, TX 77843-2128, USA. fitzpat@tamu.edu
authors.forename: Paul F
authors.initials: PF
authors.lastname: Fitzpatrick
authors.forename: Allen M
authors.initials: AM
authors.lastname: Orville
authors.forename: Akanksha
authors.initials: A
authors.lastname: Nagpal
authors.forename: Michael P
authors.initials: MP
authors.lastname: Valley
mesh_terms: D042964:Acyl-CoA Dehydrogenase / Q000737:chemistry*; D000595:Amino Acid Sequence; D019943:Amino Acid Substitution; D000818:Animals; D001224:Aspartic Acid / Q000378:metabolism; D001665:Binding Sites; D002384:Catalysis; D049308:Dioxygenases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D004980:Ethane / Q000031:analogs & derivatives* / Q000378:metabolism; D005420:Flavoproteins / Q000737:chemistry*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009595:Nitroparaffins / Q000378:metabolism; D011485:Protein Binding; D017386:Sequence Homology, Amino Acid; D013379:Substrate Specificity
chemical_list: D005420:Flavoproteins; D009595:Nitroparaffins; D001224:Aspartic Acid; C014705:nitroethane; D049308:Dioxygenases; C021876:2-nitropropane dioxygenase; D042964:Acyl-CoA Dehydrogenase; D004980:Ethane