First paragraph (this article has no abstract) Transglutaminase (protein-glutamine:amine γ-glutamyl-transferase, E.C. 2.3.2.13) catalyses acyl-transfer reactions between γ-carboxyamide groups of glutamine residues and the ε -amino group of lysines in proteins, leading to inter- or intramolecular cross-linking. Transglutaminases (TGs) have been found in mammals, plants, fish, nematodes and bacteria. Two maize cDNA clones (TGZ15 and TGZ21) that expressed active transglutaminase localized in chloroplasts were isolated [1,2].Peer reviewed