title: [Cathepsin D from horse spleen. I. Purification and study of certain physicochemical properties].
abstract: Horse spleen cathepsin D (3.4.23.5.) was purified from crude extract by sodium chloride and ethanol precipitation, column chromatography fractionation on DEAE cellulose and CM Sephadex, re-chromatography on DEAE cellulose and gel filtration. The enzyme has been purified about 3.000 folds with a yield of 30 per cent. The purified enzyme seems to be homogeneous on Sephadex G100, one protein band is apparent on disc electrophoresis. Determined by dansylation the N-terminal amino acid is glycine. A molecular weight of 42,500 +/- 3,000 was obtained with Sephadex G100 gel filtration and light scattering measurements. Amino acid analysis and chemical determinations were performed: cathepsin D is a glycoprotein (2 or 3 osamine residues) including 344 amino acids and 4 disulfide bonds. Spectrophotometric data show that E1cm/1 mg/ml = 1.01 at lambda = 280 nm. ORD measurements indicate about 20 per cent of helicoidal content in the molecule.
mesh_terms: D000596:Amino Acids / Q000032:analysis; D000818:Animals; D002403:Cathepsins / Q000302:isolation & purification; D002848:Chromatography, DEAE-Cellulose; D002850:Chromatography, Gel; D004591:Electrophoresis, Polyacrylamide Gel; D006023:Glycoproteins; D006736:Horses; D008970:Molecular Weight; D009905:Optical Rotatory Dispersion; D011487:Protein Conformation; D013056:Spectrophotometry, Ultraviolet; D013154:Spleen / Q000201:enzymology*
chemical_list: D000596:Amino Acids; D006023:Glycoproteins; D002403:Cathepsins
vernacular_title: La cathepsine D de rate de cheval. I. Purification et étude de quelques propriétés physico-chimiques