Enzymes

Enzymes are proteins produced by living organisms and which function as biochemical catalysts to increase the rate of a chemical reaction without themselves being destroyed or altered upon completion of the reactions. The human body probably contains about 10,000 different enzymes. Enzymes work by binding molecules so that they are held in a particular geometric configuration that allows the reaction to occur.

Enzymes are very specific; few molecules closely fit the binding site. Each enzyme catalyzes a specific type of chemical reaction between a few closely related compounds, which are called substrates of the enzyme.

Enzymes serve a wide variety of functions inside living organisms. They are indispensable for signal transduction, cell regulation and they generate muscle contraction. Another important function of enzymes is in the digestive systems. Enzymes such as amylases and proteases break down large molecules (starch or proteins, respectively) into smaller ones, so they can be absorbed by the intestines. Different enzymes digest different food substances.

Outside of the body, enzymes are used commercially in a variety of industries, including food processing (e.g. turning starch into sugars, such as high-fructose corn syrup), the brewing of beer, dairy (think blue cheese), paper, biofuels, and molecular biology. Enzymes are also involved in a wide variety of healthcare applications, including in pharmacology, in the synthesis of antibiotics, and in the manipulation of DNA in genetic engineering. Enzymes are also involved in more exotic functions, such as light in fireflies.