Enzymes are almost exclusively proteins (with the exception of ribozymes) that accelerate chemical reactions by lowering the required for a reaction to proceed.

The addition or removal of chemical groups (like phosphorylation) acts as a molecular "toggle switch."

Produce large quantities of rare enzymes for industrial or medical use.

Their activity can be switched on or off, allowing the cell to respond to environmental changes. 2. Molecular Architecture and the Active Site

Specific residues within the active site participate directly in the making and breaking of chemical bonds.

Many enzymes require non-protein helpers, such as metal ions (Zn²⁺, Mg²⁺) or organic molecules (NADH, FADH₂), to function.

Use laboratory techniques to "evolve" enzymes that can break down plastics or synthesize complex pharmaceuticals. Conclusion