Glutaminyl cyclase

From Proteopedia

spinqualitylabelsall models Structure of human glutaminyl cyclase complex with benzyimidazole and Zn+2 ion (PDB code 2afx). Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image Function Glutaminyl cyclase (QC) or glutaminyl-peptide cyclotransferase catalyzes the conversion of glutaminyl-peptide to 5-oxoprolyl-peptide and ammonia. Thus QC catalyzes the cyclization of an N-terminal glutamyl residue[1]. Relevance The biological assembly of Human Glutaminyl cyclase is . QC is considered as a marker of thyroid tumors. QC acts on the generation of N-terminal pyroglutamyl groups of peptide hormones and amyloid-related plaque-forming peptides. The latter contributes to Alzheimer disease. Alzheimer patients show increased expression of QC[2] and QC inhibitors reduces the disease pathology and symptoms. Structural highlights The [3].

3D Structures of glutaminyl cyclase

Updated on 17-July-2025

References

1. ↑ Busby WH Jr, Quackenbush GE, Humm J, Youngblood WW, Kizer JS. An enzyme(s) that converts glutaminyl-peptides into pyroglutamyl-peptides. Presence in pituitary, brain, adrenal medulla, and lymphocytes. J Biol Chem. 1987 Jun 25;262(18):8532-6. PMID:3597387
2. ↑ Valenti MT, Bolognin S, Zanatta C, Donatelli L, Innamorati G, Pampanin M, Zanusso G, Zatta P, Dalle Carbonare L. Increased glutaminyl cyclase expression in peripheral blood of Alzheimer's disease patients. J Alzheimers Dis. 2013;34(1):263-71. doi: 10.3233/JAD-120517. PMID:23207485 doi:http://dx.doi.org/10.3233/JAD-120517
3. ↑ Huang KF, Liu YL, Cheng WJ, Ko TP, Wang AH. Crystal structures of human glutaminyl cyclase, an enzyme responsible for protein N-terminal pyroglutamate formation. Proc Natl Acad Sci U S A. 2005 Sep 13;102(37):13117-22. Epub 2005 Aug 31. PMID:16135565