Compounds I of catalase and horse radish peroxidase: pi-cation radicals.

Compounds I of Catalase and Horse Radish Peroxidase : 7 r - Cation Radicals

Two-electron oxidation of cobaltous actaethylporphyrin [Co(II)(Et).P] yields a stable ...... cation radical [Co(III)(Et)8P]'+·, the optical spectrum of which exhibits spectral changes dependent upon the nature of the counterion. COInparison of these spectra with those of Compounds I of horseradish peroxidase and catalase leads us to propose that these Compounds I contain a 7r-cation radical of ...

Substituted hemins as probes for structure-function relationships in horseradish peroxidase.

Low temperature visible spectra of Compounds I from peroxidases reconstituted with protohemin, 2-formyl-4-vinyldeuterohemin, 2-vinyl-4-formyldeuterohemin, 2,4-dimethyldeuterohemin, and 2,4-diacetyldeuterohemin reveal that these Fe(IV) porphyrin pi-cation radicals take the 2A2u of peroxidase-type electronic ground state. Compound I of deuterohemin horseradish peroxidase, however, takes the 2A1u ...

Purification of horse-radish peroxidase and comparison of its properties with those of catalase and methaemoglobin.

Resonance Raman spectra of horseradish peroxidase and bovine liver catalase compound I species. Evidence for predominant 2A2u pi-cation radical ground state configurations.

The nature of the porphyrin pi-cation radicals in the horseradish peroxidase and bovine liver catalase (BLC) compound I species have been investigated by studying their resonance Raman spectra. A variety of laser excitation and sample interrogation procedures have been employed in order to minimize previously documented problems arising from photoinduced conversions. With Soret band excitation,...

The oxidation of tyramine, tyrosine, and related compounds by peroxidase.

Horse-radish peroxidase in the presence of hydrogen peroxide has been reported to act directly upon tyrosine, tryptophan, and cystine, but no reaction products have thus far been identified (I). Tyrosine is of special interest since it has been suggested (1, 2) that the inactivation of certain biologically active proteins by peroxidase depends in part upon oxidation of tyrosyl groups present in...