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Crystal Structure of Selenomethionine-incorporated Nicotine Oxidoreductase from Pseudomonas putidaCrystal Structure of Selenomethionine-incorporated Nicotine Oxidoreductase from Pseudomonas putida
Structural highlights
FunctionNICA2_PSEP6 Involved in nicotine degradation (PubMed:24204321, PubMed:26237398, PubMed:29812904, PubMed:33432238). Catalyzes the conversion of nicotine to N-methylmyosmine (PubMed:24204321, PubMed:29812904, PubMed:33432238, PubMed:33464876). N-methylmyosmine undergoes spontaneous hydrolysis to form pseudooxynicotine (PN) (PubMed:24204321). S-nicotine is the optimal substrate (PubMed:29812904). Has lower activity with some nicotine analogs, but shows no activity towards neurotransmitters, including serotonin, dopamine, and norepinephrine, nicotine metabolites and common neuroactive drugs (PubMed:29812904). The enzyme is stereospecific with poor activity with (R)-nicotine as the substrate (PubMed:29812904). The c-type cytochrome protein CycN is the physiological electron acceptor (PubMed:33432238). O(2) is a poor electron acceptor (PubMed:33432238, PubMed:33464876).[1] [2] [3] [4] [5] Publication Abstract from PubMedThe first structure of nicotine oxidoreductase (NicA2) was determined by X-ray crystallography. Pseudomonas putida has evolved nicotine-degrading activity to provide a source of carbon and nitrogen. The structure establishes NicA2 as a member of the monoamine oxidase family. Residues 1-50 are disordered and may play a role in localization. The nicotine-binding site proximal to the isoalloxazine ring of flavin shows an unusual composition of the classical aromatic cage (W427 and N462). The active site architecture is consistent with the proposed binding of the deprotonated form of the substrate and the flavin-dependent oxidation of the pyrrolidone C-N bond followed by nonenzymatic hydrolysis. Structural Analysis Provides Mechanistic Insight into Nicotine Oxidoreductase from Pseudomonas putida.,Tararina MA, Janda KD, Allen KN Biochemistry. 2016 Dec 6;55(48):6595-6598. Epub 2016 Nov 18. PMID:27933790[6] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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