As catalase, this enzyme catalyzes the dismutation of two molecules of hydrogen peroxide to dioxygen and two molecules of water. As a peroxidase, it uses hydrogen peroxide to oxidize donor compounds and produce water. KatG from E. coli is a homotetramer with two non-covalently associated iron protoheme IX groups per tetramer, but the ortholog from Synechococcus sp. is a homodimer with one protoheme. Important sites (numbered according to E. coli KatG) include heme ligands His-106 and His-267 and active site Trp-318. Note that the translation PID:g296476 from accession X71420 from Rhodobacter capsulatus B10 contains extensive frameshift differences from the rest of the orthologous family. [Cellular processes, Detoxification]
Jiyao W et al.(2023). "The conserved domain database in 2023.",