The new sister chin polypeptide, the manufacturing method and designates the said polypeptide as the active ingredient the enzyme inhibiter

摘要

PURPOSE:To provide the subject new polypeptide extracted from the hypophysis of a salmon and purified, exhibiting an activity to inhibit the activity of enzymes containing cysteine as their active centers, such as papain and cathepsin, and useful for medicines for inhibiting the multiplication of virus as an enzyme-inhibiting agent, etc. CONSTITUTION:The objective cystatin polypeptide having an amino acid sequence of the formula is obtained by extracting the hypophysis of a female dog salmon with an ethanol extraction solvent at 4 deg.C for 14hr, the salmon having been frozen with liquid nitrogen and preserved at -80 deg.C, subjecting the obtained ethanol extract to an anion exchange chromatography, subjected the smoothly passed fraction to a cation exchange chromatography, eluting the subjected fraction with ammonium aqueous solutions having different concentrations by a stepwise method, subjecting a fraction having a cystatin activity to a gel filtration, dissolving the separated active fraction in a 0.1% trifluoroacetic acid solution, subjecting the solution to reverse phase high performance chromatography, eluting the subjected fraction with 0.1% trifluoroacetic acid-containing acetonitrile solutions having a linear concentration gradient of 20-50%, and subsequently lyophilizing the separated active fraction.