Chemical nature of the porphyrin .pi. cation radical in horseradish peroxidase compound I
- 27 September 1983
- journal article
- research article
- Published by American Chemical Society (ACS) in Biochemistry
- Vol. 22 (20) , 4769-4774
- https://doi.org/10.1021/bi00289a024
Abstract
The EPR and Mossbauer properties of native horseradish peroxidase have been compared with those of a synthetic derivative of the enzyme in which a mesohemin residue replaces the natural Fe protoporphyrin IX heme prosthetic group. The oxyferryl .pi. cation radical intermediate, compound I, was formed from both the native and synthetic enzyme, and the magnetic properties of both intermediates were examined. The optical absorption characteristics of compound I prepared from mesoheme-substituted horseradish peroxidase are different from those of the compound I prepared from native enzyme [DiNello et. Dolphin (1981)]. Possibly these optical absorption differences are due to the formation of an A2u and an A1u .pi. cation radical species, respectively. The EPR and Mossbauer properties of the native and synthetic enzyme and of their oxidized intermediates are quite similar, if not identical, and the data favor an A2u radical for both compounds I.This publication has 14 references indexed in Scilit:
- Spectrum of chloroperoxidase compound IBiochemical and Biophysical Research Communications, 1980
- Electron-nuclear double resonance of the hydrogen peroxide compound of cytochrome c peroxidase: identification of the free radical site with a methionyl cluster.Proceedings of the National Academy of Sciences, 1979
- The missing heme spin state and a model for cytochrome c'. The mixed S = 3/2, 5/2 intermediate spin ferric porphyrin: perchlorato(meso-tetraphenylporphinato)iron(III)Journal of the American Chemical Society, 1979
- The role of protein and porphyrin in the reactivity of horseradish peroxidase toward hydrogen donorsBiochemical and Biophysical Research Communications, 1979
- Mössbauer spectroscopic study of compound es of cytochrome c peroxidaseBiochimica et Biophysica Acta (BBA) - General Subjects, 1976
- Peroxidase Isozymes from Horseradish RootsJournal of Biological Chemistry, 1966
- STUDIES ON CYTOCHROME C PEROXIDASE .2. STOICHIOMETRY BETWEEN ENZYME H2O2 AND FERROCYTOCHROME C AND ENZYMIC DETERMINATION OF EXTINCTION COEFFICIENTS OF CYTOCHROME C1965
- The chemical nature of the second hydrogen peroxide compound formed by cytochrome c peroxidase and horseradish peroxidase. 1. Titration with reducing agentsBiochemical Journal, 1953
- The transition from the primary to the secondary peroxidase-peroxide complexArchives of Biochemistry and Biophysics, 1952
- Purification of horse-radish peroxidase and comparison of its properties with those of catalase and methaemoglobinBiochemical Journal, 1951