Protein-glutamine gamma-glutamyltransferase

In enzymology, a protein-glutamine gamma-glutamyltransferase is an enzyme that catalyzes the chemical reaction


 * protein glutamine + alkylamine $$\rightleftharpoons$$ protein N5-alkylglutamine + NH3

Thus, the two substrates of this enzyme are protein glutamine and alkylamine, whereas its two products are protein N5-alkylglutamine and NH3.

This enzyme belongs to the family of transferases, specifically the aminoacyltransferases. The systematic name of this enzyme class is protein-glutamine:amine gamma-glutamyltransferase. Other names in common use include transglutaminase, Factor XIIIa, fibrinoligase, fibrin stabilizing factor, glutaminylpeptide gamma-glutamyltransferase, polyamine transglutaminase, tissue transglutaminase, and R-glutaminyl-peptide:amine gamma-glutamyl transferase. This enzyme participates in complement and coagulation cascades and huntington's disease. It employs one cofactor, calcium.

Structural studies
As of late 2007, 19 structures have been solved for this class of enzymes, with PDB accession codes, , , , , , , , , , , , , , , , , , and.