Abstract |
Golgi mannosidase II (GMII) catalyzes the sequential hydrolysis of two mannosyl residues from GlcNAcMan5GlcNAc2 to produce GlcNAcMan3GlcNAc2, the precursor for all complex N- glycans, including the branched N- glycans associated with cancer. Inhibitors of GMII are potential cancer therapeutics, but their usefulness is limited by off-target effects, which produce α- mannosidosis-like symptoms. Despite many structural and mechanistic studies of GMII, we still lack a potent and selective inhibitor of this enzyme. Here, we synthesized manno-epi- cyclophellitol epoxide and aziridines and demonstrate their covalent modification and time-dependent inhibition of GMII. Application of fluorescent manno-epi- cyclophellitol aziridine derivatives enabled activity-based protein profiling of α- mannosidases from both human cell lysate and mouse tissue extracts. Synthesized probes also facilitated a fluorescence polarization-based screen for dGMII inhibitors. We identified seven previously unknown inhibitors of GMII from a library of over 350 iminosugars and investigated their binding modalities through X-ray crystallography. Our results reveal previously unobserved inhibitor binding modes and promising scaffolds for the generation of selective GMII inhibitors.
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Authors | Zachary Armstrong, Chi-Lin Kuo, Daniël Lahav, Bing Liu, Rachel Johnson, Thomas J M Beenakker, Casper de Boer, Chung-Sing Wong, Erwin R van Rijssel, Marjoke F Debets, Bogdan I Florea, Colin Hissink, Rolf G Boot, Paul P Geurink, Huib Ovaa, Mario van der Stelt, Gijsbert M van der Marel, Jeroen D C Codée, Johannes M F G Aerts, Liang Wu, Herman S Overkleeft, Gideon J Davies |
Journal | Journal of the American Chemical Society
(J Am Chem Soc)
Vol. 142
Issue 30
Pg. 13021-13029
(07 29 2020)
ISSN: 1520-5126 [Electronic] United States |
PMID | 32605368
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- Cyclohexanols
- Enzyme Inhibitors
- cyclophellitol
- Mannosidases
- mannosyl-oligosaccharide 1,3 - 1,6-alpha-mannosidase
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Topics |
- Cyclohexanols
(chemical synthesis, chemistry, pharmacology)
- Drug Discovery
- Enzyme Inhibitors
(chemical synthesis, chemistry, pharmacology)
- Humans
- Mannosidases
(antagonists & inhibitors, metabolism)
- Molecular Structure
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