General term for enzymes cleaving N-acetylhexose ( e.g., N-acetylglucosamine) residues from gangliosidelike oligosaccharides. At least four specific enzymes carrying out this type of reaction are known: α-N-acetyl-d-galactosaminidase, α-N-acetyl-d-glucosaminidase, β-N-acetyl-d-h., and β-N-acetyl-d-galactosaminidase, each being specific for the configuration and type of sugar included in the name.
- h. A a hydrolytic enzyme that acts on ganglioside GM2, producing N-acetyl-d-galactosamine and ganglioside GM3; a deficiency of this enzyme is associated with Tay-Sachs disease.
- h. B a hydrolytic enzyme that acts on ganglioside GM1, producing ganglioside GM1 and galactose, as well as on globoside, producing N-acetylgalactosamine and trihexosylceramide; a deficiency of this enzyme is associated with Sandhoff disease.
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hex·os·a·min·i·dase .hek-.säs-ə-'min-ə-.dās, -.dāz n either of two hydrolytic enzymes that catalyze the splitting off of a hexose from a ganglioside and are deficient in some metabolic diseases:
a) HEXOSAMINIDASE A
b) HEXOSAMINIDASE B
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hex·os·amin·i·dase (hek″sōs-ə-minґĭ-dās) 1. any of the enzymes that cleave hexosamine or N-acetylhexosamine residues from gangliosides or other glycosides. Specific enzymes are named for the specific amino sugar and linkage that are potential substrates (e.g., α-N-acetylglucosaminidase). 2. β-N-acetylhexosaminidase.Medical dictionary. 2011.