title: Differentiation of two variants of type-AB GM2-gangliosidosis using chromogenic substrates.
abstract: Two variants of type-ABGM2-gangliosidosis can be distinguished by using p-nitrophenyl-6-sulfo-2-acetamido-2-deoxy-beta-D-glucopyranoside (PNP-GlcNAc-6-SO4) as substrate. One of the variants is caused by a deficiency of the activator for the hydrolysis of GM2-ganglioside. The beta-hexosaminidase A from this variant has a normal activity toward both PNP-GlcNAc and PNP-GlcNAc-6-SO4. A second variant caused by a defect in the enzyme, beta-hexosaminidase A, exhibits severely attenuated activity toward PNP-GlcNAc-6-SO4 but normal activity toward PNP-GlcNAc.
mesh_terms: D000117:Acetylglucosamine / Q000031:analogs & derivatives; D001921:Brain / Q000201:enzymology / Q000378:metabolism; D002675:Child, Preschool; D002863:Chromogenic Compounds; D005678:G(M2) Ganglioside / Q000378:metabolism; D006596:Hexosaminidases / Q000378:metabolism; D006801:Humans; D013661:Tay-Sachs Disease / Q000235:genetics* / Q000378:metabolism; D001619:beta-N-Acetylhexosaminidases
chemical_list: D002863:Chromogenic Compounds; D005678:G(M2) Ganglioside; C038069:4-nitrophenyl-6-sulfo-2-acetamido-2-deoxyglucose; D006596:Hexosaminidases; D001619:beta-N-Acetylhexosaminidases; D000117:Acetylglucosamine