Many regulatory proteins, such as kinases and phosphatases, contain phosphopeptide recognition domains known as fork-head association (FHA) domains (IPR000253). Most of the conserved residues in metalloenzyme (IPR006124) and alkaline phosphatase are likely involved in metal binding and catalysis. The phosphatase activator SpoIIE N (IPR045768) is essential for enzyme activity. Carbohydrate binding domain 20 (CBM20) (PS51166) is one region of amylolytic enzymes is similar to that of other enzymes in the family. Enzymes that break down starch and glycogen are collectively referred to as amylase.