Peptide synthesis in organic media with subtilisin 72 immobilized on poly(vinyl alcohol)-cryogel carrier

Serine proteinase subtilisin 72 was covalently attached to the beads of pol y(vinyl alcohol)-cryogel, a macroporous hydrogel prepared by the freeze-tha w technique. The immobilized enzyme was examined as a catalyst in the synth esis of protected peptides Z-Ala-Ala-Xaa-Phe-pNA (Xaa = Leu. Glu, Lys) in a cetonitrile/dimethylformamide mixtures. Immobilized subtilisin catalyzed wi th high yield the formation of peptide bonds between Phe-pNA and acyl donor s including those with free carboxylic group and non-protected C-terminal b asic and acidic amino acid residues. (C) 2001 Elsevier Science Ltd. All rig hts reserved.