Spectral properties of myeloperoxidase and its ligand complexes

摘要: The effects of ligands with various field strengths on the optical absorption spectrum myeloperoxidase have been investigated. As is case other hemoproteins, Soret peak in spectra at 77 K moves to longer wavelengths when strong-field are present, whereas binding such as chloride and fluoride, which stabilize high-spin state, shows opposite effect. With a ligand intermediate strength, azide, not affected room temperature, but lowering temperature results formation low-spin form enzyme. Similarly, native spin state equilibrium found favoured high ionic strength displays corresponding changes spectra. From ligand- temperature-induced ferric enzyme it concluded that band 620–630 nm an α heme iron species, bands 500 690 probably ‘charge-transfer’ bands∗ state.