title: Solubilization of brush borders of hamster small intestine and fractionation of some of the components.
abstract: About 90% of the protein of hamster intestinal brush borders was solubilised in 0.25% (w/v) sodium dodecyl sulphate without total loss of biological activity. Detergent-polyacrylamide gel electrophoresis of the solubilised proteins separated 10-15 bands and partially resolved maltase, lactase, sucrase-maltase, trehalase and alkaline phosphatase activities. The disaccharidases, which were associated with the higher molecular weight proteins, were preferentially solubilised with 0.1%. (w/v) Triton X-100, butanol or papain, whereas Tris and NaI extracted only the lower molecular weight proteins, possible derived from the core filaments. Electrophoresis of brush border proteins metabolically labelled with [14-C] glucosamine suggested that many of the membrane-bound enzymes are glycoproteins. However, chromatography of a papain digest on Sephadex G-200 showed that the sucrase-maltase complex can be separated nearly free of carbohydrate without total loss of activity. The importance of characterizing membrane proteins solubilised by a number of techniques is discussed.
mesh_terms: D000469:Alkaline Phosphatase / Q000032:analysis; D000818:Animals; D000440:Butanols / Q000494:pharmacology; D002241:Carbohydrates / Q000032:analysis; D002250:Carbon Radioisotopes; D002458:Cell Fractionation; D002462:Cell Membrane / Q000032:analysis; D006224:Cricetinae; D003902:Detergents / Q000494:pharmacology; D004591:Electrophoresis, Polyacrylamide Gel; D005696:Galactosidases / Q000032:analysis; D005944:Glucosamine / Q000378:metabolism; D005959:Glucosidases / Q000032:analysis; D006023:Glycoproteins / Q000032:analysis*; D007413:Intestinal Mucosa / Q000032:analysis* / Q000648:ultrastructure; D007421:Intestine, Small / Q000032:analysis* / Q000648:ultrastructure; D007454:Iodides / Q000494:pharmacology; D008297:Male; D008722:Methods; D008854:Microscopy, Electron; D010206:Papain / Q000494:pharmacology; D012967:Sodium Dodecyl Sulfate / Q000494:pharmacology; D013393:Sucrase / Q000032:analysis; D014198:Trehalase / Q000032:analysis; D014325:Tromethamine / Q000494:pharmacology
chemical_list: D000440:Butanols; D002241:Carbohydrates; D002250:Carbon Radioisotopes; D003902:Detergents; D006023:Glycoproteins; D007454:Iodides; D014325:Tromethamine; D012967:Sodium Dodecyl Sulfate; D000469:Alkaline Phosphatase; D005696:Galactosidases; D005959:Glucosidases; D014198:Trehalase; D013393:Sucrase; D010206:Papain; D005944:Glucosamine