Enzymes that catalyze the hydrolysis of peptide bonds in proteins are called proteases or peptidases. The mechanism by which these enzymes facilitate the hydrolysis of peptide bonds involves several key steps and the participation of various biomolecules, such as amino acids, chaperones, and co-factors.1. Substrate binding: The protease recognizes and binds to the specific peptide bond in the protein substrate that needs to be cleaved. This is facilitated by the enzyme's active site, which has a specific shape and chemical environment complementary to the substrate.2. Catalysis: The protease catalyzes the hydrolysis of the peptide bond through a nucleophilic attack mechanism. This involves the donation of a pair of electrons from a nucleophile, usually a water molecule or a side chain of an amino acid residue in the enzyme's active site, to the carbonyl carbon of the peptide bond. This results in the formation of a tetrahedral intermediate.3. Proton transfer: A general acid-base catalysis mechanism is involved in the proton transfer steps. Amino acid residues in the enzyme's active site act as proton donors and acceptors, facilitating the breakdown of the tetrahedral intermediate and the release of the cleaved protein fragments.4. Product release: The cleaved protein fragments are released from the enzyme's active site, allowing the enzyme to bind to another substrate and repeat the process.Biomolecules such as amino acids, chaperones, and co-factors play crucial roles in this process:A. Amino acids: The side chains of specific amino acid residues in the enzyme's active site participate in the catalytic mechanism, acting as nucleophiles, proton donors, or proton acceptors. Additionally, amino acids in the enzyme's binding site contribute to substrate recognition and binding.B. Chaperones: Molecular chaperones are proteins that assist in the folding and assembly of other proteins, including proteases. They help maintain the correct three-dimensional structure of the enzyme, which is essential for its catalytic activity.C. Co-factors: Some proteases require co-factors, which are non-protein molecules that bind to the enzyme and are essential for its activity. Co-factors can be metal ions e.g., zinc in metalloproteases or organic molecules e.g., coenzyme A in serine proteases . These co-factors can participate in the catalytic mechanism or stabilize the enzyme's structure.In summary, the hydrolysis of peptide bonds in proteins by proteases is a complex process involving substrate recognition, catalysis, and product release. Amino acids, chaperones, and co-factors play essential roles in maintaining the enzyme's structure and facilitating the catalytic mechanism.