protein glutamine + alkylamine = protein N5-alkylglutamine + NH3
the first step in both types of modifications is the acylation of the active site cysteine (Cys277) of TG2 by a protein-bound glutamine residue, resulting in the liberation of ammonia and the formation of a thioester intermediate between TG2 and the glutamine bearing protein substrate. In TG2 catalyzed transamidation, the thioester intermediate is attacked by a nucleophilic primary amine, either a small molecule amine such as putrescine or the epsilon-amino group of protein-bound lysine residues. This results in the formation of relatively stable isopeptide bonds
Please wait a moment until the data is sorted. This message will disappear when the data is sorted.
Requires Ca2+. The gamma-carboxamide groups of peptide-bound glutamine residues act as acyl donors, and the 6-amino-groups of protein- and peptide-bound lysine residues act as acceptors, to give intra- and inter-molecular N6-(5-glutamyl)-lysine crosslinks. Formed by proteolytic cleavage from plasma Factor XIII