@article{aea2bd9d952540c791b4706308f7b5fa,
title = "Human glucocerebrosidase mediates formation of xylosylcholesterol by β-xylosidase and transxylosidase reactions",
abstract = "Deficiency of glucocerebrosidase (GBA), a lysosomal β-glucosidase, causes Gaucher disease. The enzyme hydrolyzes β-glucosidic substrates and transglucosylates cholesterol to cholesterol-β-glucoside. Here we show that recombinant human GBA also cleaves β-xylosides and transxylosylates cholesterol. The xylosyl-cholesterol formed acts as an acceptor for the subsequent formation of di-xylosyl-cholesterol. Common mutant forms of GBA from patients with Gaucher disease with reduced β-glucosidase activity were similarly impaired in β-xylosidase, transglucosidase, and transxylosidase activities, except for a slightly reduced xylosidase/glucosidase activity ratio of N370S GBA and a slightly reduced transglucosylation/ glucosidase activity ratio of D409H GBA. XylChol was found to be reduced in spleen from patients with Gaucher disease. The origin of newly identified XylChol in mouse and human tissues was investigated. Cultured human cells exposed to exogenous β-xylosides generated XylChol in a manner dependent on active lysosomal GBA but not the cytosol-facing β-glucosidase GBA2.Welater sought an endogenous β-xyloside acting as donor in transxylosylation reactions, identifying xylosylated ceramide (XylCer) in cells and tissues that serve as donor in the formation of XylChol. UDP-glucosylceramide synthase (GCS) was unable to synthesize XylChol but could catalyze the formation of XylCer. Thus, foodderived β-D-xyloside and XylCer are potential donors for the GBA-mediated formation of XylChol in cells. The enzyme GCS produces XylCer at a low rate. Our findings point to further catalytic versatility of GBA and prompt a systematic exploration of the distribution and role of xylosylated lipids.",
keywords = "Ceramides, Cerebrosides, Gaucher disease, Glycolipids, Inborn errors of metabolism, Metabolism, XYLOSYLATION",
author = "Boer, {Daphne E.} and Mina Mirzaian and Ferraz, {Maria J.} and Zwiers, {Kimberley C.} and Baks, {Merel V.} and Hazeu, {Marc D.} and Roelof Ottenhoff and Marques, {Andre R. A.} and Rianne eijer and Roos, {Jonathan C. P.} and Cox, {Timothy M.} and Boot, {Rolf G.} and Navraj Pannu and Overkleeft, {Herman S.} and Marta Artola and Aerts, {Johannes M.}",
note = "Funding Information: 25-[N-[(7-nitro-2-1,3-benzoxadiazol-4-yl)methyl]amino]-27-norcholesterol (25-NBDcholesterol) and ceramide d18:1/18:1 was purchased from Avanti Polar Lipids (Alabaster, AL). (6-((N-(7-Nitrobenz-2-Oxa-1,3-Diazol-4-yl)amino)hexanoyl)sphingosine) (NBD C6-Ceramide) was purchased from Invitrogen (Waltham, MA). 4-Methylumbelliferyl β-D-glucoside (4-MU-Glc) and 4-methylumbelliferyl β-D-xyloside (4-MU-Xyl) were purchased from Glycosynth{\texttrademark} (Cheshire, United Kingdom). Cyanidin-3-O-β-D-xyloside was obtained from Toronto Research Chemicals (North York, Canada). Uridine diphosphate glucose (UDPGlc), cholesterol, cholesterol trafficking inhibitor U18666A, 1-O-cholesteryl-β-D-glucose (βcholesteryl glucose, β-GlcChol), and ammonium formate (LC-MS quality) were from Sigma-Aldrich (St Louis, MO). Uridine diphospho- α-D-xylopyranoside (UDP-Xyl) was purchased from Carbo-Source Services (Athens, Supported in part by Grant #DE-FG02-93ER20097). GBA inhibitor Conduritol-β-epoxide (L-1,2-anhydro-myo-inositol; CBE) was purchased from Enzo Life Sciences Inc. (Farmingdale, NY), GBA inhibitor ME656 (16) GBA2 inhibitor N-(5-adamantane-1-yl-methoxy-pentyl)-deoxynojirimycin (AMP-DNM) (17), D-xylo-cyclophellitol, ceramide d17:0/16:0, and 13C6-GlcChol were synthesized at Leiden Institute of Chemistry (Leiden, The Netherlands) (10, 18, 19). Cerezyme{\textregistered}, a recombinant human GBA (rhGBA) was obtained from Genzyme (Genzyme Nederland, Naarden, The Netherlands). LC-MS-grade methanol, 2-propanol, water, and HPLC-grade chloroform were purchased from Biosolve. XylChol was synthesized as described in supplemental materials and methods. Funding Information: The study was supported by a grant to J. M. A from NWO Building Blocks of Life (Glucosylceramide: 737.016.002). Publisher Copyright: {\textcopyright} 2021 American Society for Biochemistry and Molecular Biology Inc.. All rights reserved.",
year = "2021",
doi = "https://doi.org/10.1194/JLR.RA120001043",
language = "English",
volume = "62",
journal = "Journal of Lipid Research",
issn = "0022-2275",
publisher = "American Society for Biochemistry and Molecular Biology Inc.",
}