Catalase-like heme-binding proteins similar to the uncharacterized srpA
Catalase is a ubiquitous enzyme found in both prokaryotes and eukaryotes involved in the protection of cells from the toxic effects of peroxides. It catalyses the conversion of hydrogen peroxide to water and molecular oxygen. Several other related protein families share the catalase fold and bind to heme, but do not necessarily have catalase activity. This family contains uncharacterized proteins similar to the Synechococcus elongatus PCC 7942 periplasmic protein srpA, of mostly bacterial origin. The plasmid-encoded srpA is regulated by sulfate, but does not seem to function in its uptake or metabolism.