How Enzymes Are Biological Catalysts

Enzymes are biological catalysts, meaning that they speed up chemical processes in our bodies by lowering the activation energy required for them to take place. Like chemical catalysts, enzymes take place in the reaction, however, remain unchanged at the end. In humans, enzymes are involved in nearly all of the biological processes required for us to live. All known enzymes are proteins, hence are made up from chains of amino acids. They have an active site, which is the part of the molecule where the reaction takes place. This reacting molecule that binds to the enzyme is called the substrate. The reaction containing the enzyme occurs in two stages where s represents the substrate, E the enzyme and P the product, E + S ↔ ES ↔ E + P. Enzyme catalyzed reactions can be either anabolic or catabolic. Anabolic reactions are those where small molecules are linked together to form large complex molecules. Conversely,

If the conditions are not desirable for the enzyme, it will perform at a slower rate, or denature. For both enzyme and substrate concentration, an increase in concentration will result in increased activity until the optimal point. Enzymes tend to perform best at higher temperatures, until reaching their optimal point. After this point their behavior rapidly worsens until they denature. Enzymes also have an optimal pH range. Outside of this range, the reaction rate will slow, and the enzyme will potentially denature.
Inhibitors, both competitive and non-competitive, act to lower to catalytic activity of an enzyme. Competitive inhibitors are substances which are similar enough to the substrate that they can occupy the active site, hence preventing a substrate from combining with an enzyme. Non-competitive inhibitors occupy a different site on the enzyme, preventing the binding of the substrate by altering the active site of an