title: Studies of the cell surface of Paramecium. Ciliary membrane proteins and immobilization antigens.
abstract: We have developed a procedure to isolate the ciliary membranes of Paramecium and have analysed the membrane proteins by electrophoresis on polyacrylamide gels containing either Triton X-100 or sodium dodecyl sulphate. The electrophoretic pattern on gels containing sodium dodecyl sulphate showed 12-15 minor bands of mol.wt. 25 000-150 000 and on major band of mol.wt. 200 000-300 000 that contained approximately three-quarters of the total membrane protein. 2. We present evidence that the major membrane protein is related to, but not identical with, the immobilization antigen (i-antigen), which is a large (250 000 mol.w.), soluble, surface protein of Paramecium. The similarity of the i-antigen and the major membrane protein was shown by immunodiffusion and by the electrophoretic mobilities in sodium dodecyl sulphate of these two proteins from Paramecium of serotypes A and B. The non-identity of these two proteins was shown by their different electrophoretic mobilities on Triton X-100 containing gels and their different solubilities. 3. We propose that the major membrane protein and the i-antigen have a precursor-product relationship.
mesh_terms: D000941:Antigens / Q000032:analysis*; D002923:Cilia / Q000032:analysis*; D004591:Electrophoresis, Polyacrylamide Gel; D005779:Immunodiffusion; D008566:Membranes / Q000032:analysis; D008970:Molecular Weight; D010247:Paramecium / Q000032:analysis* / Q000276:immunology; D011506:Proteins / Q000032:analysis
chemical_list: D000941:Antigens; D011506:Proteins