title: Characterization of Pseudooxynicotine Amine Oxidase of Pseudomonas putida S16 that Is Crucial for Nicotine Degradation.
abstract: Pseudooxynicotine amine oxidase (Pnao) is essential to the pyrrolidine pathway of nicotine degradation of Pseudomonas putida strain S16, which is significant for the detoxification of nicotine, through removing the CH3NH2 group. However, little is known about biochemical mechanism of this enzyme. Here, we characterized its properties and biochemical mechanism. Isotope labeling experiments provided direct evidence that the newly introduced oxygen atom in 3-succinoylsemialdehyde-pyridine is derived from H2O, but not from O2. Pnao was very stable at temperatures below 50 °C; below this temperature, the enzyme activity increased as temperature rose. Site-directed mutagenesis studies showed that residue 180 is important for its thermal stability. In addition, tungstate may enhance the enzyme activity, which has rarely been reported before. Our findings make a further understanding of the crucial Pnao in nicotine degradation.
authors.affiliation: State Key Laboratory of Microbial Metabolism, and School of Life Sciences &Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China.|Joint International Research Laboratory of Metabolic &Developmental Sciences, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China.
authors.forename: Haiyang
authors.initials: H
authors.lastname: Hu
authors.affiliation: State Key Laboratory of Microbial Metabolism, and School of Life Sciences &Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China.|Joint International Research Laboratory of Metabolic &Developmental Sciences, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China.
authors.forename: Weiwei
authors.initials: W
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Microbial Metabolism, and School of Life Sciences &Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China.|Joint International Research Laboratory of Metabolic &Developmental Sciences, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China.
authors.forename: Hongzhi
authors.initials: H
authors.lastname: Tang
authors.affiliation: State Key Laboratory of Microbial Metabolism, and School of Life Sciences &Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China.|Joint International Research Laboratory of Metabolic &Developmental Sciences, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China.
authors.forename: Ping
authors.initials: P
authors.lastname: Xu
mesh_terms: D000588:Amines / Q000737:chemistry; D002074:Butanones / Q000737:chemistry / Q000378:metabolism; D053858:Metabolic Networks and Pathways; D008995:Monoamine Oxidase / Q000737:chemistry / Q000378:metabolism*; D009538:Nicotine / Q000031:analogs & derivatives / Q000737:chemistry / Q000378:metabolism*; D010100:Oxygen / Q000737:chemistry / Q000378:metabolism*; D016958:Pseudomonas putida / Q000201:enzymology*; D011759:Pyrrolidines / Q000378:metabolism; D014867:Water / Q000737:chemistry
chemical_list: D000588:Amines; D002074:Butanones; D011759:Pyrrolidines; D014867:Water; C081694:pseudooxynicotine; D009538:Nicotine; D008995:Monoamine Oxidase; C032519:pyrrolidine; D010100:Oxygen