Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.21 (beta-glucosidase)
 3,280 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Gaucher disease is caused by mutations in the gene encoding acid-beta-glucosidase. A recombinant form of this enzyme, Cerezyme, is used to treat Gaucher disease patients by ;enzyme-replacement therapy'. Crystals of Cerezyme after its partial deglycosylation were obtained earlier and the structure was solved to 2.0 A resolution [Dvir et al. (2003), EMBO Rep. 4, 704-709]. The crystal structure of unmodified Cerezyme is now reported, in which a substantial number of sugar residues bound to three asparagines via N-glycosylation could be visualized. The structure of intact fully glycosylated Cerezyme is virtually identical to that of the partially deglycosylated enzyme. However, the three loops at the entrance to the active site, which were previously observed in alternative conformations, display additional variability in their structures. Comparison of the structure of acid-beta-glucosidase with that of xylanase, a bacterial enzyme from a closely related protein family, demonstrates a close correspondence between the active-site residues of the two enzymes.
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PMID:Structural comparison of differently glycosylated forms of acid-beta-glucosidase, the defective enzyme in Gaucher disease. 1713 81

The non-random association of Gaucher disease with polyclonal and monoclonal gammopathy has been known since 1950. The effect of treatment on monoclonal gammopathy is not well documented. We report on the long-term evolution of a biclonal gammopathy in a patient with type I Gaucher disease who was treated with splenectomy and enzyme replacement therapy. A 44-year-old man presented with hepatomegaly and massive splenomegaly. Bone marrow aspirate contained typical Gaucher cells and beta-glucosidase was low in peripheral blood leukocytes. Mutations N370S and R120W were detected. Serum protein electrophoresis disclosed two spikes in gammaglobulins. Immunofixation identified two monoclonal components: IgG kappa and IgA kappa. Gammaglobulin concentration was 31.6 g/L. A splenectomy was performed on September 2003 because of massive splenomegaly (9500 g). Two months after the splenectomy, gammaglobulin concentration was 25.2 g/L. Enzyme replacement therapy (Cerezyme 45 UI/kg every two weeks) was prescribed from April 2004 because of significant hepatomegaly and cholestasis. In April 2007 (3 years after the beginning of treatment), serum electrophoresis showed the persistence of two spikes with gammaglobulin concentration at 20.5 g/L. Simultaneously, chitotriosidase activity decreased from 6181 to 2877 nkat/L. Our observation and previous reports suggest that enzyme replacement therapy is more effective in polyclonal hypergammaglobulinaemia than in monoclonal gammopathy.
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PMID:Effect of treatment on biclonal gammopathy associated with Gaucher disease. 1787 46

Gaucher disease, the most common lysosomal storage disease, can be treated with enzyme replacement therapy (ERT), in which defective acid-beta-glucosidase (GlcCerase) is supplemented by a recombinant, active enzyme. The X-ray structures of recombinant GlcCerase produced in Chinese hamster ovary cells (imiglucerase, Cerezyme) and in transgenic carrot cells (prGCD) have been previously solved. We now describe the structure and characteristics of a novel form of GlcCerase under investigation for the treatment of Gaucher disease, Gene-Activated human GlcCerase (velaglucerase alfa). In contrast to imiglucerase and prGCD, velaglucerase alfa contains the native human enzyme sequence. All three GlcCerases consist of three domains, with the active site located in domain III. The distances between the carboxylic oxygens of the catalytic residues, E340 and E235, are consistent with distances proposed for acid-base hydrolysis. Kinetic parameters (K(m) and V(max)) of velaglucerase alfa and imiglucerase, as well as their specific activities, are similar. However, analysis of glycosylation patterns shows that velaglucerase alfa displays distinctly different structures from imiglucerase and prGCD. The predominant glycan on velaglucerase alfa is a high-mannose type, with nine mannose units, while imiglucerase contains a chitobiose tri-mannosyl core glycan with fucosylation. These differences in glycosylation affect cellular internalization; the rate of velaglucerase alfa internalization into human macrophages is at least 2-fold greater than that of imiglucerase.
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PMID:Characterization of gene-activated human acid-beta-glucosidase: crystal structure, glycan composition, and internalization into macrophages. 1974 Oct 58