How can the function of proteins and enzymes be mediated?

The function of proteins and enzymes is significantly influenced by structural changes that can occur through various mechanisms, which include both cleavage and a combination of non-covalent and covalent interactions.

Proteins and enzymes are dynamic molecules whose activities can be altered by changes in their three-dimensional structures. These structural changes may be induced by different factors:

1. Covalent interactions: These are strong chemical bonds that can stabilize or rearrange the protein structure, resulting in a functional change. For example, phosphorylation can activate or deactivate enzymes, reflecting a covalent modification.

2. Non-covalent interactions: These include hydrogen bonds, ionic bonds, van der Waals forces, and hydrophobic interactions. Non-covalent interactions are vital for maintaining the protein's tertiary structure and can be reversible. Changes in substrate concentrations, pH, or temperature can lead to alterations in these interactions, affecting the protein's activity.

3. Cleavage: Certain proteins and enzymes require cleavage for their activation. For example, zymogens (inactive enzyme precursors) must be cleaved to become active enzymes, showing how structural changes via cleavage are crucial for functionality.

By considering both types of interactions and the role of structural modification via cleavage,