COMPARATIVE HYDROLYSIS OF GELATIN BY PEPSIN, TRYPSIN, ACID, AND ALKALI.

Area of Science:

• Biochemistry
• Protein Chemistry
• Enzymology

Background:

• Gelatin, a collagen derivative, contains various peptide linkages.
• Understanding the differential hydrolysis of these linkages is crucial for protein chemistry.

Purpose of the Study:

• To compare the relative hydrolysis rates of different peptide linkages in gelatin.
• To investigate the distinct and overlapping specificities of acid, alkali, pepsin, and trypsin in gelatin hydrolysis.

Main Methods:

• Comparative analysis of gelatin hydrolysis kinetics.
• Enzymatic (pepsin, trypsin) and chemical (acid, alkali) hydrolysis experiments were conducted.

Main Results:

• Linkages rapidly cleaved by pepsin or trypsin were resistant to acid hydrolysis.
• Pepsin and trypsin hydrolyzed overlapping sets of linkages, with trypsin acting on additional sites.
• Linkages targeted by pepsin or trypsin were among the first to be hydrolyzed by alkali.
• Early-stage gelatin hydrolysis followed similar patterns with alkali, pepsin, and trypsin, but differed markedly with acid.

Conclusions:

• Acid hydrolysis of gelatin proceeds via a distinct mechanism compared to enzymatic or alkaline hydrolysis.
• Pepsin and trypsin exhibit specific yet partially overlapping substrate specificities on gelatin.
• Alkali hydrolysis shares similarities with enzymatic hydrolysis in the early stages of gelatin breakdown.