title: [Inactivation of o-diphenoloxidase in the pyrocatechol oxidation reaction].
abstract: The inactivation kinetics of o-diphenoloxidase isolated from potato tubers was studied in the process of pyrocatechol oxidation. The enzyme when saturated with the substrate is inactivated with the inactivation rate constant kin = 0.5-1.0 min-1; kin depends on the initial concentration of pyrocatechol. The ultimate yield of the enzymic reaction product increases linearly with the initial concentration of the enzyme. Introduction of ethylene-diaminosulphate, a substance which condenses with o-quinones, does not increase the operation stability of o-diphenoloxidase. The data obtained evidence for inactivation of o-diphenoloxidase either at the level of the enzyme-substrate complex or due to bimolecular reaction with the substrate.
mesh_terms: D004156:Catechol Oxidase / Q000037:antagonists & inhibitors*; D002396:Catechols / Q000378:metabolism*; D066298:In Vitro Techniques; D007700:Kinetics; D014442:Monophenol Monooxygenase / Q000037:antagonists & inhibitors* / Q000378:metabolism; D010084:Oxidation-Reduction; D013379:Substrate Specificity
chemical_list: D002396:Catechols; D004156:Catechol Oxidase; D014442:Monophenol Monooxygenase; C034221:catechol
vernacular_title: Inaktivatsiia o-difenoloksidazy v protsesse reaktsii okisleniia pirokatekhina.