Formation of reactive halide species by myeloperoxidase and eosinophil peroxidase

Arch Biochem Biophys. 2006 Jan 15;445(2):225-34. doi: 10.1016/j.abb.2005.06.025. Epub 2005 Jul 28.

Abstract

The formation of chloro- and bromohydrins from 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine following incubation with myeloperoxidase or eosinophil peroxidase in the presence of hydrogen peroxide, chloride and/or bromide was analysed by matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry. These products were only formed below a certain pH threshold value, that increased with increasing halide concentration. Thermodynamic considerations on halide and pH dependencies of reduction potentials of all redox couples showed that the formation of a given reactive halide species in halide oxidation coupled with the reduction of compound I of heme peroxidases is only possible below a certain pH threshold that depends on halide concentration. The comparison of experimentally derived and calculated data revealed that Cl(2), Br(2), or BrCl will primarily be formed by the myeloperoxidase-H(2)O(2)-halide system. However, the eosinophil peroxidase-H(2)O(2)-halide system forms directly HOCl and HOBr.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alcohols / chemical synthesis*
  • Chlorohydrins / chemical synthesis*
  • Computer Simulation
  • Eosinophil Peroxidase / chemistry*
  • Halogens / chemical synthesis
  • Hydrogen Peroxide / chemistry*
  • Hydrogen-Ion Concentration
  • Models, Chemical*
  • Oxidation-Reduction
  • Peroxidase / chemistry*
  • Phosphatidylcholines / chemistry*
  • Thermodynamics

Substances

  • Alcohols
  • Chlorohydrins
  • Halogens
  • Phosphatidylcholines
  • bromohydrins
  • Hydrogen Peroxide
  • Eosinophil Peroxidase
  • Peroxidase
  • 1-palmitoyl-2-oleoylphosphatidylcholine