Catalase family
catalase family
Catalases are heme-containing anti-oxidative enzymes. Although classed as peroxidases by the enzyme commission they are distinct from other heme peroxidases. Both use H2O2 as an oxidant as a first step; however, catalases specifically oxidize H2O2 in the next step, thereby generating two molecules of water and oxygen by consuming two molecules of H2O2, while peroxidases oxidize other organic and inorganic substrates. Catalases have a distinct fold and evolutionary origin from the animal heme peroxidase family. There is only one catalase gene in the human genome.