Transglutaminase is an enzyme that forms crosslinks between protein molecules. Transglutaminase catalyses the formation of an isopeptide bond between the group of γ-carboxamides of glutamine residues and the first-order ε-amine groups of different compounds. Transglutaminase is involved in many physiological processes, including coagulation, antibacterial immune reactions and photosynthesis.In Vitro: Transglutaminase activity can be increased by Co2+, Ba2+ and K+.
Microbial transglutaminases are inhibited by Zn2+, Cu2+, Hg2+ and Pb2+ ions which bind to the thiol group of cysteine in the active centre.