Human O-GlcNAcase Uses a Preactivated Boat-skew Substrate Conformation for Catalysis. Evidence from X-ray Crystallography and QM/MM Metadynamics

CALVELO, Martín, MALES, Alexandra, ALTEEN, Matthew G, WILLEMS, Lianne I, VOCADLO, David J, DAVIES, Gideon J and ROVIRA, Carme (2023). Human O-GlcNAcase Uses a Preactivated Boat-skew Substrate Conformation for Catalysis. Evidence from X-ray Crystallography and QM/MM Metadynamics. ACS Catalysis, 13 (20), 13672-13678.

Preview

PDF Males-HumanO-GlcNAcase(VoR).pdf - Published Version Creative Commons Attribution. Download (4MB) | Preview

Abstract

Human O-linked β-N-acetylglucosaminidase (hOGA) is one of the two enzymes involved in nuclear and cytoplasmic protein O-GlcNAcylation, an essential post-translational modification. The enzyme catalyzes the hydrolysis of the GlcNAc-O-(Ser/Thr) glycosidic bonds via anchimeric assistance through the 2-acetamido group of the GlcNAc sugar. However, the conformational itinerary of the GlcNAc ring during catalysis remains unclear. Here we report the crystal structure of wild type hOGA in complex with a nonhydrolyzable glycopeptide substrate and elucidate the full enzyme catalytic mechanism using QM/MM metadynamics. We show that the enzyme can bind the substrate in either a chair- or a boat-like conformation, but only the latter is catalytically competent, leading to the reaction products via 1,4B/1S3 → [4E]‡ → 4C1 and 4C1 → [4E]‡ → 1,4B/1S3 conformational itineraries for the first and second catalytic reaction steps, respectively. Our results reconcile previous experimental observations for human and bacterial OGA and will aid the development of more effective OGA inhibitors for diseases associated with impaired O-GlcNAcylation.

Item Type:	Article
Uncontrolled Keywords:	0302 Inorganic Chemistry; 0305 Organic Chemistry; 0904 Chemical Engineering; 3106 Industrial biotechnology; 3405 Organic chemistry; 3406 Physical chemistry
Identification Number:	https://doi.org/10.1021/acscatal.3c02378
Page Range:	13672-13678
SWORD Depositor:	Symplectic Elements
Depositing User:	Symplectic Elements
Date Deposited:	26 Mar 2024 11:06
Last Modified:	28 Mar 2024 11:32
URI:	https://shura.shu.ac.uk/id/eprint/33470

Actions (login required)

View Item

Downloads

Publication Metrics