1y7v
From Proteopedia
X-ray structure of human acid-beta-glucosidase covalently bound to conduritol B epoxide
Structural highlights
DiseaseGBA1_HUMAN Gaucher disease type 3;Gaucher disease-ophthalmoplegia-cardiovascular calcification syndrome;Gaucher disease type 1;Hereditary late-onset Parkinson disease;Gaucher disease type 2;Fetal Gaucher disease;NON RARE IN EUROPE: Dementia with Lewy body;NON RARE IN EUROPE: Parkinson disease. The disease is caused by variants affecting the gene represented in this entry. The disease is caused by variants affecting the gene represented in this entry. The disease is caused by variants affecting the gene represented in this entry. The disease is caused by variants affecting the gene represented in this entry. The disease is caused by variants affecting the gene represented in this entry. The disease is caused by variants affecting the gene represented in this entry. Perinatal lethal Gaucher disease is associated with non-immune hydrops fetalis, a generalized edema of the fetus with fluid accumulation in the body cavities due to non-immune causes. Non-immune hydrops fetalis is not a diagnosis in itself but a symptom, a feature of many genetic disorders, and the end-stage of a wide variety of disorders.[1] Disease susceptibility may be associated with variants affecting the gene represented in this entry. FunctionGBA1_HUMAN Glucosylceramidase that catalyzes, within the lysosomal compartment, the hydrolysis of glucosylceramides/GlcCers (such as beta-D-glucosyl-(1<->1')-N-acylsphing-4-enine) into free ceramides (such as N-acylsphing-4-enine) and glucose (PubMed:15916907, PubMed:24211208, PubMed:32144204, PubMed:9201993). Plays a central role in the degradation of complex lipids and the turnover of cellular membranes (PubMed:27378698). Through the production of ceramides, participates in the PKC-activated salvage pathway of ceramide formation (PubMed:19279011). Catalyzes the glucosylation of cholesterol, through a transglucosylation reaction where glucose is transferred from GlcCer to cholesterol (PubMed:24211208, PubMed:26724485, PubMed:32144204). GlcCer containing mono-unsaturated fatty acids (such as beta-D-glucosyl-N-(9Z-octadecenoyl)-sphing-4-enine) are preferred as glucose donors for cholesterol glucosylation when compared with GlcCer containing same chain length of saturated fatty acids (such as beta-D-glucosyl-N-octadecanoyl-sphing-4-enine) (PubMed:24211208). Under specific conditions, may alternatively catalyze the reverse reaction, transferring glucose from cholesteryl 3-beta-D-glucoside to ceramide (Probable) (PubMed:26724485). Can also hydrolyze cholesteryl 3-beta-D-glucoside producing glucose and cholesterol (PubMed:24211208, PubMed:26724485). Catalyzes the hydrolysis of galactosylceramides/GalCers (such as beta-D-galactosyl-(1<->1')-N-acylsphing-4-enine), as well as the transfer of galactose between GalCers and cholesterol in vitro, but with lower activity than with GlcCers (PubMed:32144204). Contrary to GlcCer and GalCer, xylosylceramide/XylCer (such as beta-D-xyosyl-(1<->1')-N-acylsphing-4-enine) is not a good substrate for hydrolysis, however it is a good xylose donor for transxylosylation activity to form cholesteryl 3-beta-D-xyloside (PubMed:33361282).[2] [3] [4] [5] [6] [7] [8] [9] [10] Evolutionary ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedGaucher disease is an inherited metabolic disorder caused by mutations in the lysosomal enzyme acid-beta-glucosidase (GlcCerase). We recently determined the x-ray structure of GlcCerase to 2.0 A resolution (Dvir, H., Harel, M., McCarthy, A. A., Toker, L., Silman, I., Futerman, A. H., and Sussman, J. L. (2003) EMBO Rep.4, 704-709) and have now solved the structure of Glc-Cerase conjugated with an irreversible inhibitor, conduritol-B-epoxide (CBE). The crystal structure reveals that binding of CBE to the active site does not induce a global conformational change in GlcCerase and confirms that Glu340 is the catalytic nucleophile. However, only one of two alternative conformations of a pair of flexible loops (residues 345-349 and 394-399) located at the entrance to the active site in native GlcCerase is observed in the GlcCerase-CBE structure, a conformation in which the active site is accessible to CBE. Analysis of the dynamics of these two alternative conformations suggests that the two loops act as a lid at the entrance to the active site. This possibility is supported by a cluster of mutations in loop 394-399 that cause Gaucher disease by reducing catalytic activity. Moreover, in silico mutational analysis demonstrates that all these mutations stabilize the conformation that limits access to the active site, thus providing a mechanistic explanation of how mutations in this loop result in Gaucher disease. X-ray structure of human acid-beta-glucosidase covalently bound to conduritol-B-epoxide. Implications for Gaucher disease.,Premkumar L, Sawkar AR, Boldin-Adamsky S, Toker L, Silman I, Kelly JW, Futerman AH, Sussman JL J Biol Chem. 2005 Jun 24;280(25):23815-9. Epub 2005 Apr 6. PMID:15817452[11] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See Also
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