title: Degradation of band-3 glycoprotein in vitro by a protease isolated from human erythrocyte membrane.
abstract: The use of soybean-trypsin-inhibitor-Sepharose-4B to purify a protease present in human erythrocyte membranes is described. The fraction bound in the presence of calcium to the affinity absorbent is active on band-3 glycoprotein in a non-ionic detergent solution at neutral pH. Band-3 glycoprotein is degraded into components having the mobilities of the proteins of bands 4.5, 7 and of lower molecular weights. When calcium is omitted from the membrane extract, an inactive form of this enzyme can be purified. By DEAE-cellulose chromatography this inactive form can be converted into the active form, presumably by dissociation of an enzyme-inhibitor complex.
mesh_terms: D001457:Anion Exchange Protein 1, Erythrocyte; D001798:Blood Proteins / Q000378:metabolism*; D002846:Chromatography, Affinity; D004910:Erythrocyte Membrane / Q000201:enzymology*; D004912:Erythrocytes / Q000201:enzymology*; D006801:Humans; D066298:In Vitro Techniques; D010447:Peptide Hydrolases / Q000097:blood* / Q000302:isolation & purification; D014361:Trypsin Inhibitors
chemical_list: D001457:Anion Exchange Protein 1, Erythrocyte; D001798:Blood Proteins; D014361:Trypsin Inhibitors; D010447:Peptide Hydrolases