A Specific Activity-Based Probe to Monitor Family GH59 Galactosylceramidase, the Enzyme Deficient in Krabbe Disease

作者：Marques Andre R A; Willems Lianne I; Moro Daniela Herrera; Florea Bogdan I; Scheij Saskia; Ottenhoff Roelof; van Roomen Cindy P A A; Verhoek Marri; Nelson Jessica K; Kallemeijn Wouter W; Biela Banas Anna; Martin Olivier R; Cachon Gonzalez M Begona; Kim Nee Na; Cox Timothy M; Boot Rolf G; Overkleeft Herman S^*; Aerts Johannes M F G^*

来源：ChemBioChem, 2017, 18(4): 402-412.

DOI：10.1002/cbic.201600561

• beta-galactosidase
• fluorescent probes
• galactosylceramidase
• hydrolase
• Krabbe disease

Galactosylceramidase (GALC) is the lysosomal beta-galactosidase responsible for the hydrolysis of galactosylceramide. Inherited deficiency in GALC causes Krabbe disease, a devastating neurological disorder characterized by accumulation of galactosylceramide and its deacylated counterpart, the toxic sphingoid base galactosylsphingosine (psychosine). We report the design and application of a fluorescently tagged activity-based probe (ABP) for the sensitive and specific labeling of active GALC molecules from various species. The probe consists of a beta-galactopyranose- configured cyclophel litol-epoxide core, conferring specificity for GALC, equipped with a BODIPY fluorophore at C6 that allows visualization of active enzyme in cells and tissues. Detection of residual GALC in patient fibroblasts holds great promise for laboratory diagnosis of Krabbe disease. We further describe a procedure for in situ imaging of active GALC in murine brain by intra-cerebroventricular infusion of the ABP. In conclusion, this GALC-specific ABP should find broad applications in diagnosis, drug development, and evaluation of therapy for Krabbe disease.

• 出版日期2017-2-16