Chymopapain and method of purifying it on an inhibitory dipeptide affinity column

摘要

PCT No. PCT/EP90/00647 Sec. 371 Date Dec. 13, 1991 Sec. 102(e) Date Dec. 13, 1991 PCT Filed Apr. 27, 1990 PCT Pub. No. WO90/13561 PCT Pub. Date Nov. 15, 1990.A method of purifying chymopapain by active site directed affinity chromatography using inhibitory dipeptides as affinity ligands is presented. The inhibitory dipeptides have C-terminal aldehyde derivatives of phenylalanine selected from the group consisting of the semicarbazone, the methoxyimine and the oxime. The purified chymopapain has a specific activity against BAPNA (1 mM) at 40 DEG C. and pH 6.8 of between 3000 and 4500 units per mg and contains less than 0.2% each of papaya proteinase III (PPIII), papain and papaya proteinase IV (PPIV). The use of purified chymopapain in pharmaceutical compositions for the treatment of damaged mammalian spinal discs is also disclosed.