How do enzymes facilitate chemical reactions?

Enzymes play a critical role in facilitating chemical reactions primarily by lowering the activation energy required for those reactions to occur. Activation energy is the minimum amount of energy needed to initiate a chemical reaction, and by reducing this barrier, enzymes enable the reaction to proceed more efficiently and at a faster rate. This lowering of activation energy does not change the overall energy of the reactants and products but makes it easier for the reactants to reach the transition state, leading to a more favorable environment for the reaction to take place.

The mechanism through which enzymes perform this action involves the formation of enzyme-substrate complexes, where the enzyme binds to its specific substrate. This binding can stabilize the transition state or bring substrates closer together in the correct orientation, further promoting the reaction. Enzymes are not consumed in the reaction; they remain unchanged and can catalyze the reaction repeatedly.