Iodoacetamide

Iodoacetamide: IAN is an irreversible inhibitor of many cysteine proteases. However, it is not highly specific for the active site cysteine residue of proteases and can inhibit many enzymes. In the alkylation reaction, IAN reacts with histidine (such as in RNase), methionine and sulfhydryl groups of many proteins. IAN can react with low molecular weight thiol compounds such as mercaptoethanol and glutathione. The reaction of IAN with glutathione was utilized in a titration method for the determination of sulfhydryl groups in different compounds. The alkylation reaction forms stable protein derivatives which will remain intact during further study of the protein.