title: Human senile cataractous lens protease. Isolation and some chemical characteristics.
abstract: A proteolytic enzyme was isolated from human senile cataractous lens by anion-exchange and gel-filtration chromatography. Sedimentation and zone-electrophoretic experiments indicated a high degree of homogeneity for the enzyme. A molecular weight of 27000 was calculated from measurements of sedimentation velocity and diffusion coefficient. Chelating agents decreased activity which could be restored by addition of certain bivalent metal ions. Di-isopropyl phosphorofluoridate and phenylmethanesulphonyl fluoride inhibit the proteolytic activities. Optimum rates of hydrolysis were observed at pH5.2.
mesh_terms: D000368:Aged; D000596:Amino Acids / Q000032:analysis; D002386:Cataract / Q000201:enzymology*; D002850:Chromatography, Gel; D002852:Chromatography, Ion Exchange; D003035:Cobalt; D004058:Diffusion; D004589:Electrophoresis, Disc; D005459:Fluorides; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007531:Isoflurophate; D007908:Lens, Crystalline / Q000201:enzymology*; D008345:Manganese; D008970:Molecular Weight; D009532:Nickel; D010447:Peptide Hydrolases / Q000032:analysis / Q000302:isolation & purification*; D011480:Protease Inhibitors; D013696:Temperature; D014461:Ultracentrifugation
chemical_list: D000596:Amino Acids; D011480:Protease Inhibitors; D007531:Isoflurophate; D003035:Cobalt; D008345:Manganese; D009532:Nickel; D010447:Peptide Hydrolases; D005459:Fluorides