Iodoacetamide is an alkylation agent by reacting with histidine, methionine and sulfhydryl groups of proteins. It is an irreversible inhibitor of all cysteine proteases by alkylation of the catalytic cysteine residue, including deubiquitinating enzymes (DUBs), Cathepsin B, and beta-Amylase. It also inhibits ribonuclease by reacting with histidine residues (occurring at a much slower rate than cysteine). Under limiting quantities and a slightly alkaline pH, Iodoacetamide exclusively reacts with cysteines in proteins.
