title: Transient kinetics of copper-containing lentil (Lens culinaris) seedling amine oxidase.
abstract: The reaction between lentil (Lens culinaris) seedling amine oxidase and its chromogenic substrate, p-dimethylaminomethylbenzylamine, has been studied by the stopped-flow technique. Upon being mixed with substrate in the absence of oxygen, the enzyme is bleached in a complex kinetic process. A yellow intermediate absorbing at 464 nm and the first product (aldehyde) are formed in subsequent steps. When oxygenated buffer is mixed with substrate-reduced amine oxidase, the 496 nm absorption of the oxidized enzyme is very rapidly restored in a second-order process (k = 2.5 X 10(7) M-1 X S-1). This reaction is appreciable even at very low oxygen concentration, in keeping with the fairly low Km for O2 measured by steady-state kinetics.
mesh_terms: D006631:Amine Oxidase (Copper-Containing); D000693:Anaerobiosis; D001596:Benzylamines / Q000378:metabolism; D003300:Copper / Q000378:metabolism*; D007887:Fabaceae / Q000201:enzymology*; D007700:Kinetics; D000587:Oxidoreductases Acting on CH-NH Group Donors / Q000378:metabolism*; D010100:Oxygen / Q000378:metabolism; D010946:Plants, Medicinal; D013053:Spectrophotometry; D013997:Time Factors
chemical_list: D001596:Benzylamines; C002000:4-dimethylaminomethylbenzylamine; D003300:Copper; D006631:Amine Oxidase (Copper-Containing); D000587:Oxidoreductases Acting on CH-NH Group Donors; D010100:Oxygen