title: Use of 4-heptylumbelliferyl-beta-D-glucoside to identify Gaucher's disease heterozygotes.
abstract: Three fluorometric beta-glucosidase assays were compared for their ability to identify Gaucher's disease heterozygotes, using leukocytes as the source of enzyme: the pH 5.5-taurocholate assay of Peters et al.; the conduritol B epoxide dependent variation of that assay; and the newly developed method described herein. While the first two procedures utilize the standard substrate 4-methylumbelliferyl-beta-D-glucopyranoside to estimate beta-glucosidase activity, the new assay uses 4-heptylumbelliferyl-beta-D-glucoside as (C7UGlc) substrate. Use of this substrate enhances the specificity of the method for lysosomal glucocerebrosidase, thereby minimizing the contribution of the nonspecific cytosolic beta-glucosidase to estimates of substrate hydrolysis. Using Student's t test for the three assays examined, the C7UGlc assay procedure was determined to have the lowest p value (p less than 0.001) and highest t value (t = 4.95) for the discrimination between the mean glucocerebrosidase value of control and obligate Gaucher heterozygote samples. The high reliability and simplicity of the C7UGlc assay lends adequate reason to favor this assay for regular clinical diagnosis of Gaucher heterozygotes.
authors.affiliation: Department of Microbiology, Biochemistry and Molecular Biology, University of Pittsburgh School of Medicine, PA.
authors.forename: B A
authors.initials: BA
authors.lastname: Butcher
authors.forename: V
authors.initials: V
authors.lastname: Gopalan
authors.forename: R E
authors.initials: RE
authors.lastname: Lee
authors.forename: T C
authors.initials: TC
authors.lastname: Richards
authors.forename: A S
authors.initials: AS
authors.lastname: Waggoner
authors.forename: R H
authors.initials: RH
authors.lastname: Glew
mesh_terms: D001921:Brain / Q000201:enzymology; D005776:Gaucher Disease / Q000235:genetics*; D006580:Genetic Carrier Screening / Q000379:methods*; D005962:Glucosylceramidase / Q000378:metabolism; D006801:Humans; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D007124:Immunoenzyme Techniques; D007294:Inositol / Q000031:analogs & derivatives; D007962:Leukocytes / Q000201:enzymology; D008099:Liver / Q000201:enzymology; D010920:Placenta / Q000201:enzymology; D013656:Taurocholic Acid; D014468:Umbelliferones; D001617:beta-Glucosidase / Q000097:blood
chemical_list: D014468:Umbelliferones; C062569:4-heptylumbelliferyl-beta-glucoside; D007294:Inositol; D013656:Taurocholic Acid; D001617:beta-Glucosidase; D005962:Glucosylceramidase; C011423:conduritol epoxide