title: S1 pocket of glutamate carboxypeptidase II: a new binding site for amyloid-β degradation.
abstract: We recently reported that glutamate carboxypeptidase II (GCPII) has a new physiological function degrading amyloid-β (Aβ), distinct from its own hydrolysis activity in N-acetyl-L-aspartyl-L-glutamate (NAAG); however, its underlying mechanism remains undiscovered. Using site-directed mutagenesis and S1 pocket-specific chemical inhibitor (compound 2), which was developed for the present study based on in sillico computational modeling, we discovered that the Aβ degradation occurs through S1 pocket but not through S1' pocket responsible for NAAG hydrolysis. Treatment with compound 2 prevented GCPII from Aβ degradation without any impairment in NAAG hydrolysis. Likewise, 2-PMPA (specific GCPII inhibitor developed targeting S1' pocket) completely blocked the NAAG hydrolysis without any effect on Aβ degradation. Pre-incubation with NAAG and Aβ did not affect Aβ degradation and NAAG hydrolysis, respectively. These data suggest that GCPII has two distinctive binding sites for two different substrates and that Aβ degradation occurs through binding to S1 pocket of GCPII.
authors.affiliation: Division of Brain Diseases, Center for Biomedical Science, Korea National Institute of Health, Osong, Chungcheongbuk-do 363-951, South Korea.
authors.forename: Suk Kyung
authors.initials: SK
authors.lastname: Lee
authors.forename: Hyunyoung
authors.initials: H
authors.lastname: Kim
authors.forename: You-Hoon
authors.initials: YH
authors.lastname: Cheong
authors.forename: Min-Ju
authors.initials: MJ
authors.lastname: Kim
authors.forename: Sangmee Ahn
authors.initials: SA
authors.lastname: Jo
authors.forename: Hyung-Seop
authors.initials: HS
authors.lastname: Youn
authors.forename: Sang Ick
authors.initials: SI
authors.lastname: Park
mesh_terms: D000544:Alzheimer Disease / Q000201:enzymology* / Q000378:metabolism; D016229:Amyloid beta-Peptides / Q000378:metabolism*; D000818:Animals; D001665:Binding Sites / Q000187:drug effects; D045744:Cell Line, Tumor; D004151:Dipeptides / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000494:pharmacology; D043425:Glutamate Carboxypeptidase II / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D018698:Glutamic Acid / Q000378:metabolism; D006801:Humans; D051379:Mice; D008822:Mice, Transgenic; D062105:Molecular Docking Simulation; D016297:Mutagenesis, Site-Directed; D009943:Organophosphorus Compounds / Q000494:pharmacology; D059748:Proteolysis / Q000187:drug effects
chemical_list: C402107:2-(phosphonomethyl)pentanedioic acid; D016229:Amyloid beta-Peptides; D004151:Dipeptides; D004791:Enzyme Inhibitors; D009943:Organophosphorus Compounds; C027172:isospaglumic acid; D018698:Glutamic Acid; D043425:Glutamate Carboxypeptidase II
keywords: Alzheimer’s diseases; Amyloid-beta; Binding site; GCPII; S1 pocket