A certain species of bacteria secretes an enzyme which causes deactivation of several α-amylases. This enzyme seems to be an adaptive enzyme formed against these α-amylases. Enzymatical studies show that the enzyme is sensitive to heat, acid, and alkali; the optimum pH of its activity is at about 5.2; it requires phosphates as a cofactor in order to display its enzymatic action, and as the enzyme deactivates α-amylases, titratable acid is formed.
