[Mechanism of the antimicrobial action of myeloperoxidase. The role of adsorption of the enzyme on the target cell surface].

Myeloperoxidase (MPO), obtained from the granular fraction of bovine neutrophils at low concentrations (3 nm), exerted antibiotic influence on E. coli. After treatment with the MPO3 - H2O2 - Cl- system the number of living cells in the suspension dropped to 4.7% of the initial value. The preliminary treatment of MPO with antibodies at high concentrations, thus preventing MPO from being adsorbed on the surface of bacterial cells without suppressing its enzymatic catalytic activity, resulted in the considerable decrease of its bactericidal effect. These results suggest that the adsorption of MPO on the surface of target cells is the essential condition of its antimicrobial action.