Inhibition of catechol 2,3-dioxygenase from Pseudomonas putida by 3-chlorocatechol.

摘要: Partially purified preparations of catechol 2,3-dioxygenase from toluene-grown cells Pseudomonas putida catalyzed the stoichiometric oxidation 3-methylcatechol to 2-hydroxy-6-oxohepta-2,4-dienoate. Other substrates oxidized by enzyme preparation were catechol, 4-methylcatechol, and 4-fluorocatechol. The apparent Michaelis constants for 10.6 22.0 muM, respectively. Substitution at 4-position decreases affinity activity substrate. Catechol did not oxidize 3-chlorocatechol. In addition, incubation with 3-chlorocatechol led inactivation enzyme. Kinetic analyses revealed that both 4-chlorocatechol noncompetitive or mixed-type inhibitors 3-Chlorocatechol (Ki = 0.14 muM) was a more potent inhibitor than 50 muM). effect ion-chelating agents Tiron o-phenanthrolene compared on Each appeared remove iron enzyme, since inactive could be fully reactivated treatment ferrous reducing agent.