Reaction: (1) D-glutamine + D-glutamate = NH3 + γ-D-glutamyl-D-glutamate
(2) L(or D)-glutamine + (γ-D-glutamyl)n-[peptide] = ammonia + (γ-D-glutamyl)n+1-[peptide]
Other name(s): D-glutamyl transpeptidase; D-γ-glutamyl transpeptidase
Systematic name: L(or D)-glutamine
Comments: The enzyme catalyses two reactions. The first is the transfer of a glutamyl residue from L- or D-glutamine to D-glutamate via a γ linkage, forming γ-glutamyl-D-glutamate, and the second is the transfer of additional glutamyl residues to the peptide, extending the polypeptide chain.
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 9030-02-8
References:
1. Williams, W.J. and Thorne, C.B. Biosynthesis of glutamyl peptides from glutamine by a transfer reaction. J. Biol. Chem. 210 (1954) 203-217. [PMID: 13201582]
2. Williams, W.J., Litwin, J. and Thorne, C.B. Further studies on the biosynthesis of γ-glutamyl peptides by transfer reactions. J. Biol. Chem. 212 (1955) 427-438. [PMID: 13233245]