Removal of H(2)O(2), oxidation of toxic reductants, biosynthesis and degradation of lignin, suberization, auxin catabolism, response to environmental stresses such as wounding, pathogen attack and oxidative stress. These functions might be dependent on each isozyme/isoform in each plant tissue. 2 a phenolic donor + H2O2 = 2 a phenolic radical donor + 2 H2O Binds 1 heme b (iron(II)-protoporphyrin IX) group per subunit. Binds 2 calcium ions per subunit. Carboxy-terminal extension appears to target the protein to vacuoles. By methyl jasmonate, a plant defense-related signaling molecule. There are 73 peroxidase genes in A.thaliana. Belongs to the peroxidase family. Classical plant (class III) peroxidase subfamily.