PEPTIDE-SYNTHESIS CATALYZED BY CROSS-LINKED ALPHA-CHYMOTRYPSIN IN WATER DIMETHYLFORMAMIDE SOLVENT SYSTEM

alpha-Chymotrypsin was crosslinked to give a water-insoluble polymer by treatment with the bifunctional reagent glutaraldehyde, The specific activity of the crosslinked enzyme in aqueous media was three orders of magnitude lower than for the native chymotrypsin. In a medium containing more than 50% (v/v) of dimethylformamide the specific activities of both enzymes were comparable. In addition, the insoluble polymer was more stable in the presence of 60% (v/v) dimethylformamide compared with the native enzyme. Therefore, in this medium enzymatic peptide synthesis could be successfully accomplished with the crosslinked enzyme, but not with the same amount of native chymotrypsin.