[Protein hydrolysis by immobilized enzymes]

Area of Science:

• Biochemistry
• Enzymology
• Protein Chemistry

Background:

• Traditional acid hydrolysis of proteins can lead to partial destruction of certain amino acids.
• Specific amino acids like tryptophan and methionine are particularly susceptible to degradation during acid hydrolysis.
• Immobilized enzymes offer potential advantages in protein hydrolysis due to stability and reusability.

Purpose of the Study:

• To investigate the efficacy of immobilized peptidolytic enzymes for protein hydrolysis.
• To compare amino acid recovery yields between enzymatic and acid hydrolysis methods.
• To assess the complete recovery of sensitive amino acids using enzymatic hydrolysis.

Main Methods:

• Proteins (insulin-B-chain-S-sulfonate, S-aminoethylated lysozyme, bovine serum albumin) were hydrolyzed using immobilized enzymes.
• Enzymes used included Sepharose-bound pronase, trypsin, Thermoactinomyces sp. protease (MP), and an exopeptidase mixture.
• Enzyme immobilization involved methods such as cross-linking with glutaric dialdehyde and binding to Sepharose.

Main Results:

• Enzymatic hydrolysis achieved nearly 100% recovery of most amino acids compared to acid hydrolysis.
• Proline was the only amino acid not recovered at 100% yield.
• Complete recovery of tryptophan and methionine was achieved, which are typically degraded by acid hydrolysis.

Conclusions:

• Immobilized peptidolytic enzymes provide a highly efficient method for protein hydrolysis.
• Enzymatic hydrolysis is superior to acid hydrolysis for preserving sensitive amino acids.
• This method ensures complete recovery of all amino acids, including tryptophan and methionine.