Haem peroxidase superfamily
IPR010255
Definition
Peroxidases are haem-containing enzymes that use hydrogen peroxide as the electron acceptor to catalyse a number of oxidative reactions. Most haem peroxidases follow the reaction scheme: Fe3++ H2O2-->[Fe4+=O]R' (Compound I) + H2O [Fe4+=O]R' + substrate -->[Fe4+=O]R (Compound II) + oxidised substrate [Fe4+=O]R + substrate -->Fe3++ H2O + oxidised substrate In this mechanism, the enzyme reacts with one equivalent of H2O2to give [Fe4+=O]R' (compound I). This is a two-electron oxidation/reduction reaction where H2O2is reduced to water and the enzyme is oxidised. One oxidising equivalent resides on iron, giving the oxyferryl PMID:8062820 intermediate, while in many peroxidases the porphyrin (R) is oxidised to the porphyrin pi-cation radical (R'). Compound I then oxidises an organic substrate to give a substrate radical PMID:7922023. Haem peroxidases include two superfamilies: one found in bacteria, fungi, plants and the second found in animals. The animal peroxidases comprise a group of homologous proteins that differ markedly from the plant/fungal/bacterial peroxidases in primary, secondary and tertiary structure, but which share with them a common function. Animal peroxidases probably arose independently of the plant/fungal/bacterial peroxidase superfamily and most likely belong to a different gene family. The crystal structures of a number of these proteins show that the active sites of animal peroxidase and plant/fungal/bacterial peroxidases are remarkably similar PMID:10403190.
10 human proteins with this domain
Each is a reviewed human protein in the Seroatlas serome and a potential autoantibody target; this domain groups them into one antibody-relevant category. Every entry links to its own record.
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