What if your body produced toxic substances everyday? Could you survive? Well, the answer is yes, you could survive. In fact your body does produce toxic substances every day. One reason they don't harm you is because of catalase. Catalase is an enzyme that destroys harmful substances inside your body. (Enzymes are substances that speed chemical reactions.) Catalase is found in nearly all living organisms. Without catalase, toxic substances could attack and mutate your DNA.
One such toxic substance is hydrogen peroxide. Hydrogen peroxide is a chemical compound with the formula H2O2. You may have seen it for sale in stores. Many people use hydrogen peroxide for sterilizing cuts, scrapes, and abrasions. There are even people who mix it with baking soda and use it while brushing their teeth. However, it's harmful inside your body and must be neutralized.
Hydrogen peroxide is produced in your body because of the reactive nature of oxygen. Earth's atmosphere is approximately 20% oxygen. We breathe it every day as part of respiration. So living with oxygen is necessary, but also dangerous. Within your cells, oxygen atoms can lose electrons. These lost electrons can then be used to produce hydrogen peroxide. Catalase can convert this dangerous hydrogen peroxide into water and oxygen gas, thereby protecting your DNA.
How It's Made
Catalase is a form of protein. In fact, all enzymes are protein. Proteins are large, globular molecules made of amino acid subunits. These amino acids are arranged in a chain to form the protein molecule. Image an actual chain. Amino acids are like the links; the chain itself is the protein.
All proteins (and enzymes) have a specific shape. This is because of how the amino acids chains are folded together. Below is a picture of the catalase enzyme. Different organisms will produce slightly different catalases. For example, the catalase found in animals is slightly different than the catalase found in plants. But the general composition remains the same. The folded and twisted segments in this image represent the amino acids chains.