[Irreversible specific inhibition of E. coli inorganic pyrophosphatase with amines]

An unusually high reactivity of the carboxyl groups of the active site of E. coli inorganic pyrophosphatase towards amines was shown. Amino acid esters and other amines are specific irreversible inhibitors of the enzyme. The reaction involves the formation of an enzyme-inhibitor complex followed by the chemical modification of dicarboxylic amino acid residues. It is assumed that the binding of the positively charged inhibitor occurs at the binding site of cations-activators.