Proteins
Proteins are the major structural component of living tissue, such as muscles, cartilage, tendons, ligaments and skin. Without proteins it is impossible for the body to heal itself after injury or to build muscle. Proteins are polymers built from small molecules called amino acids, which contain a carboxylic acid group and an amino group. An example of an amino acid is to the right.
However, it is important to note that a protein is not the same as an amino acid. In order for a protein to exist, it has to have multiple amino acids strung together in a polymer for it to be considered a protein. A single amino acid is not a protein. It is a building block of a protein. |
Protein Synthesis & Properties
Proteins are made by the condensation reaction of amino acids. The amino acids are strung together in long polymers to make the protein. In a condensation reaction, 2 amino acids come together. One amino acid loses a hydrogen from its amino and the other amino acid loses a -OH hydoxyl group, This H and OH come together to form water. What is left on the two amino acids connect to one another because of the open bonding sites. The two amino acids are now connected by a peptide bond. This process happens over and over again in order to form a long polymer of amino acids called a protein. Different proteins are made by different combinations of amino acids. There are 20 different amino acids, 9 of which are essential for use in the body. These different combinations of amino acids can form proteins as varied as muscles, hormones, enzymes and even proteins that help in reproduction.
Proteins (in the form of muscle) are burned in the body after carbohydrates and fats. To this end, a bodies first source of fuel is the carbs. Once the carbs are gone, your body will start burning stored fat in the body. Once the fat is all gone, the body will start pulling energy from proteins stored in muscles and organs. When this begins, the body starts attacking itself and destroys a persons ability to function. Proteins contain 4 Cal per gram. Proteins that you eat are broken down by the liver into simple amino acids, which can be repolymerized and used to build structural, transport, regulatory or protective proteins. Your body cannot store amino acids, so a daily requirement of proteins is necessary. |