title: Carbohydrate composition of human placental N-acetylhexosaminidase A and B.
abstract: The carbohydrate composition of N-acetyl-beta-D-hexosaminidases (EC 3.2.1.52) A, B and heat-converted B was determined by g.l.c. Similar quantities of mannose, N-acetyl-glucosamine and galactose are present in the A and B isoenzymes, whereas N-acetyl-neuraminic acid is found in significant amount in only the A isoenzyme. The heat-converted hexosaminidase B also contains only trace amounts of N-acetylneuraminic acid, but is about 1.5-fold richer in mannose and N-acetylglucosamine and nearly 2-fold richer in galactose than native hexosaminidase B. Since native and converted hexosaminidase B are thought to be composed of four identical protein chains, our results suggest that there may be variable glycosylation of these chains.
mesh_terms: D002241:Carbohydrates / Q000032:analysis*; D002849:Chromatography, Gas; D005260:Female; D006596:Hexosaminidases; D006801:Humans; D010920:Placenta / Q000201:enzymology*; D011247:Pregnancy
chemical_list: D002241:Carbohydrates; D006596:Hexosaminidases