{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T17:08:59Z","timestamp":1785431339718,"version":"3.56.0"},"reference-count":33,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2026,6,17]],"date-time":"2026-06-17T00:00:00Z","timestamp":1781654400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Institute of General Medical Sciences of the National Institutes of Health","award":["R01GM149871"],"award-info":[{"award-number":["R01GM149871"]}]},{"award":["R01GM149871"],"award-info":[{"award-number":["R01GM149871"]}],"id":[{"id":"https:\/\/ror.org\/04q48ey07","id-type":"ROR","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000001","name":"BioXFEL STC","doi-asserted-by":"publisher","award":["1231306"],"award-info":[{"award-number":["1231306"]}],"id":[{"id":"10.13039\/100000001","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>The iminosugar N-butyldeoxynojirimycin (Miglustat) is clinically used for the inhibition of ceramide glucosyltransferase for treating Type 1 Gaucher and Niemann\u2013Pick type C diseases. This drug also inhibits glycogen debranching enzyme (GDE), the enzyme responsible for terminal glycogen catabolism via coordinated glucotransferase and amylo-\u03b1-1,6-glucosidase (GC) activities, although the structural basis for inhibition has been undefined. Here, we report the crystal structure of Candida glabrata GDE in complex with Miglustat, revealing inhibitor engagement at the conserved GC domain in an area that was previously hypothesized to accommodate the \u03b1-1,6-linked glucose moiety of glycogen. Structure-guided mutagenesis demonstrates that alanine substitution of residues at the GC site abolishes Miglustat binding, functionally validating the pocket and defining the interaction hot spots. To assess the possible relevance of these observations to the human enzyme, in silico docking predicts that Miglustat binds to the human enzyme in a pose close, albeit not identical, to our structure. These findings provide an opportunity to determine the molecular basis of GDE\u2013inhibitor recognition, rationalize reported off-target effects of Miglustat, and provide a template for designing iminosugar therapies with reduced off-target binding.<\/jats:p>","DOI":"10.3390\/ijms27125490","type":"journal-article","created":{"date-parts":[[2026,6,18]],"date-time":"2026-06-18T00:49:42Z","timestamp":1781743782000},"page":"5490","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Off-Target Binding of Miglustat to Glycogen Debranching Enzyme"],"prefix":"10.3390","volume":"27","author":[{"given":"Drew","family":"Barber","sequence":"first","affiliation":[{"name":"Hauptman-Woodward Research Institute, University at Buffalo, The State University of New York, Buffalo, NY 14203, USA"},{"name":"Department of Structural Biology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, The State University of New York, Buffalo, NY 14203, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5436-7946","authenticated-orcid":false,"given":"Neha","family":"Mishra","sequence":"additional","affiliation":[{"name":"Hauptman-Woodward Research Institute, University at Buffalo, The State University of New York, Buffalo, NY 14203, USA"},{"name":"Department of Structural Biology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, The State University of New York, Buffalo, NY 14203, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fiona","family":"Hegarty","sequence":"additional","affiliation":[{"name":"Smith College, Northampton, MA 01063, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0792-492X","authenticated-orcid":false,"given":"Aviv","family":"Paz","sequence":"additional","affiliation":[{"name":"Hauptman-Woodward Research Institute, University at Buffalo, The State University of New York, Buffalo, NY 14203, USA"},{"name":"Department of Structural Biology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, The State University of New York, Buffalo, NY 14203, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,6,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"108476","DOI":"10.1016\/j.ymgme.2024.108476","article-title":"Clinical and Biochemical Footprints of Congenital Disorders of Glycosylation: Proposed Nosology","volume":"142","author":"Ng","year":"2024","journal-title":"Mol. 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