IUBMB Enzyme Nomenclature


Accepted name: γ-glutamylamine cyclotransferase

Reaction: ε-(γ-L-glutamyl)-L-lysine = L-lysine + 5-oxo-L-proline

Other name(s): GGACT

Systematic name: ε-(γ-L-glutamyl)-L-lysine γ-glutamyl cyclotransferase (5-oxo-L-proline producing)

Comments: The enzyme, found in vertebrates, has no activity toward α-(γ-L-glutamyl)-L-amino acids (cf. EC, γ-glutamylcyclotransferase). The enzyme acts as a cyclotransferase, cleaving the amide bond via transamidation using the α-amine of the γ-L-glutamyl residue, releasing it as the cyclic 5-oxo-L-proline.

Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number:


1. Fink, M.L., Chung, S.I. and Folk, J.E. γ-Glutamylamine cyclotransferase: specificity toward ε-(L-γ-glutamyl)-L-lysine and related compounds. Proc. Natl Acad. Sci. USA 77 (1980) 4564-4568. [PMID: 6107907]

2. Oakley, A.J., Coggan, M. and Board, P.G. Identification and characterization of γ-glutamylamine cyclotransferase, an enzyme responsible for γ-glutamyl-ε-lysine catabolism. J. Biol. Chem. 285 (2010) 9642-9648. [PMID: 20110353]

[EC created 2017]

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