Horseradish peroxidase is an important heme-containing enzyme that has been studied for more than a century. In recent years new information has become available on the three-dimensional structure of the enzyme and its catalytic intermediates, mechanisms of catalysis and the function of specific amino acid residues. Site-directed mutagenesis and directed evolution techniques are now used routin...

Horseradish peroxidase has been shown to catalyze the oxidation of veratryl alcohol (3,4-dimethoxybenzyl alcohol) and benzyl alcohol to the respective aldehydes in the presence of reduced glutathione, MnC12, and an organic acid metal chelator such as lactate. The oxidation is most likely the result of hydrogen abstraction from the benzylic carbon of the substrate alcohol leading to eventual dis...

Apoproteins of cytochrome c peroxidase, horseradish peroxidase, and sperm whale myoglobin were recombined with manganese complexes of proto-, hemato-, meso-, and deuteroporphyrins to form manganese porphyrin-protein complexes. These complexes were purified by column chromatography. All the manganese porphyrin-containing cytochrome c peroxidases were crystallized. Light absorption maxima of mang...

A methylene blue-mediated enzyme biosensor has been developed for the detection of inhibitors including mercury(II), mercury(I), methylmercury, and mercury–glutathione complex. The inhibition to horseradish peroxidase was apparently reversible and noncompetitive in the presence of HgCl2 in less than 8 s and irreversibly inactivated when incubated with different concentrations of HgCl2 for 1–8 m...