The catabolism of Tay-Sachs ganglioside in rat brain lysosomes.
نویسندگان
چکیده
The metabolism of Tay-Sachs ganglioside, Cer-Glc-Gal(NeuAc)-GalNAc (G& was investigated by using GNIZ specifically labeled with 3H in the NeuAc moiety or with W in GalNAc. There are two possible pathways for the catabolism of GM2 in brain, initiated via GMM-sialidase or GM2hexosaminidase. The products of the sialidase reaction were identified and are Cer-Glc-Gal-GalNAc and NeuAc; the hexosaminidase yields Cer-Glc-Gal-NeuAc and GalNAc. The pH optimum, apparent K,,,, and V,,,,, of these enzymes were determined. These findings both support the presence of two alternate pathways in mammalian brain for the catabolism of Tay-Sachs ganglioside and form a starting point for the eventual clarification of the molecular pathogenesis of Tay-Sachs disease.
منابع مشابه
The metabolism of Tay-Sachs ganglioside: catabolic studies with lysosomal enzymes from normal and Tay-Sachs brain tissue.
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ورودعنوان ژورنال:
- The Journal of biological chemistry
دوره 247 23 شماره
صفحات -
تاریخ انتشار 1972