Di. Metelitza et al., EFFECT OF MONOCLONAL-ANTIBODIES AGAINST PEROXIDASE ON PEROXIDASE-CATALYZED OXIDATION OF O-PHENYLENEDIAMINE, Biochemistry, 60(10), 1995, pp. 1269-1275
Horseradish peroxidase (HRP)-specific monoclonal antibodies (MABs) 2C,
9D, and 9F, interacting with domain I of the enzyme, have been shown
to activate HRP in the reaction of o-phenylenediamine (OPD) oxidation
at moderate H2O2 concentrations (<10 mM). In contrast, the monoclonal
antibody 3E, interacting with domain II, inhibited the oxidation of OP
D over a broad range of H2O2 concentrations. HRP-specific polyclonal a
ntibodies (PABs) were inhibitory irrespective of H2O2 Concentration. S
imilar effects were observed when OPD was oxidized by a hydrophobic co
njugate of HRP with nine molecules of cortisol. Possible mechanisms un
derlying the activation and inhibition of the enzyme are discussed.