The specificity of beta-galactosidase in the degradation of gangliosides.
Available evidence indicates that a least two genetically distinct acidic lysosomal beta-galactosidases are present in mammalian tissues. One of them, galactosylceramidase, is primarily responsible for degradation of galactosylceramide, galactosylsphingosine, and monogalactosyl-diglyceride, while the other, GM1-ganglioside beta-galactosidase, degrades GM1-ganglioside and asialo GM1-ganglioside. Lactosylceramide can be hydrolyzed by either of the two enzymes. These substrate specificities of the two beta-galactosidases can adequately explain the known findings in the two genetic beta-galactosidase deficiency diseases. The possibilities of the specific lactosylceramidase have not yet received the necessary independent confirmation.
D001921:Brain / Q000201:enzymology*; D002518:Ceramides; D005677:G(M1) Ganglioside; D005696:Galactosidases / Q000378:metabolism*; D006801:Humans; D007787:Lactose Intolerance; D013379:Substrate Specificity; D001616:beta-Galactosidase / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*
D002518:Ceramides; D005677:G(M1) Ganglioside; D005696:Galactosidases; D001616:beta-Galactosidase