[Protein hydrolysis by immobilized enzymes]

The enzymic hydrolysis of some proteins (insulin-B-chain-S-sulfonate, S-aminoethylated lysozyme, bovine serum albumin) by immobilized peptidolytic enzymes is reported. Sepharose-bound pronase, trypsin and a protease from Thermoactinomyces sp. (MP), the latter both cross linked by glutaric dialdehyde and an exopeptidase mixture containing Sepharose-bound leucine aminopeptidase, carboxypeptidase A and a crude preparation of prolidase were used. After enzymic hydrolysis nearly all amino acids, except proline, were recovered in a 100% yield compared to the value of an acid reference hydrolysate. Tryptophan and methionine, which are partially destroyed by acid hydrolysis in the presence of oxygen could be recovered completely.