Calcium dependent reversible inactivation of erythrocyte transglutaminase by acrylamide

Purified transglutaminase from human erythrocytes was shown to undergo time dependent inactivation by acrylamide added at millimolar concentration: this effect was wholly dependent on calcium ions and some protection was produced by glutamine substrates and GTP. The enzyme activity was recovered by addition of thiol based reducing agents, while ascorbic acid and sodium borohydrate were ineffective. These data are suggestive of an active site directed action of acrylamide.