Principles of Protein Structure - G. Schulz 1982

Covalent Protein Structure
Enzyme-Controlled Modifications of the Main Chain
Protein Cleavage

Degradation is just as important as synthesis. Susceptibility to inactivation and degradation is an essential biological property of all protein structures. It is believed [154–157] that the first step in protein degradation involves the Specific Cleavage of one or more peptide bonds. This is followed by extensive nonspecific proteolysis, which is the usual culmination of The breakdown of all Proteins [156]. Degradation is necessary to remove defective or currently unnecessary proteins. Another aspect is normal protein turnover, which is most critical for digestive Enzymes. If these proteins were not degraded into Amino Acids—that is, if proteases such as Trypsin and Chymotrypsin did not act as "molecular cannibals"—a human would lose 100 g of amino acids per day in the form of digestive enzymes. This amount corresponds to the protein content of a daily human diet.



Last update: 06/08/2026

Editorial and Educational Adaptation: This material has been compiled based on the primary/original source text. The project team performed an editorial review, corrected technical inaccuracies, structured sections, and adapted the content for an educational format.

What was processed:

  • elimination of formatting defects (OCR errors, structural breaks, corrupted characters);
  • editorial organization of content;
  • standardization of terminology in accordance with academic sources;
  • verification of factual statements against the original source text.

All mentions of the author, publication year, and origin of the primary text have been preserved in accordance with the source.