title: Solubilization of the membrane-bound enzymes of the brush-border plasma membrane of Hymenolepis diminuta (Cestoda) using nonionic detergents.
abstract: The ability of nonionic detergents to solubilize the membrane-bound enzymes of the brush-border plasma membrane of Hymenolepis diminuta was investigated. Of the detergents tested (Triton X-100, Tween 80, Brij 35, Lubrol PX and WX, W-1, and beta-octyl-D-glucoside), only Triton was an effective solubilizing agent. Optimal solubilization was achieved by incubating an isolated fraction of the brush-border membrane in the presence of 1% Triton X-100 for 60 min at 37 C, followed by centrifugation at 100,000 g for 60 min at 25 C. This treatment resulted in solubilization of 94% of the alkaline phosphohydrolase, 91% of the phosphodiesterase and ribonuclease, and 88% of the 5'-nucleotidase activities. The pH optima for enzymes solubilized in nonionic and ionic detergents (Triton and sodium dodecyl sulfate, respectively) did not differ. Isoelectric focusing of the Triton-solubilized material demonstrated the presence of at least 14 polypeptides, a majority of which had isoelectric points below pH 7.
mesh_terms: D000469:Alkaline Phosphatase / Q000302:isolation & purification; D000818:Animals; D002462:Cell Membrane / Q000201:enzymology; D003902:Detergents / Q000494:pharmacology*; D006926:Hymenolepis / Q000201:enzymology*; D008297:Male; D008871:Microvilli / Q000201:enzymology; D009708:Nucleotidases / Q000302:isolation & purification; D010727:Phosphoric Diester Hydrolases / Q000302:isolation & purification; D000077423:Polidocanol; D011092:Polyethylene Glycols / Q000494:pharmacology; D011136:Polysorbates / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D012260:Ribonucleases / Q000302:isolation & purification; D012995:Solubility; D013501:Surface-Active Agents / Q000494:pharmacology*
chemical_list: D003902:Detergents; D011136:Polysorbates; D013501:Surface-Active Agents; D000077423:Polidocanol; C017474:Lubrol WX; D011092:Polyethylene Glycols; D012260:Ribonucleases; D009708:Nucleotidases; D000469:Alkaline Phosphatase; D010727:Phosphoric Diester Hydrolases