20 April 2009FOOD INTOLERANCE: PROTEINS
Proteins make up our skin, hair and bones. They are major components of the nerves, blood and all other cells in the body. Specialized proteins in the muscles produce contraction by sliding over each other. Another hard-working protein, called haemoglobin, carries oxygen around in the blood, while strong, elastic proteins make up our tendons and ligaments. Chemically adept proteins known as enzymes control all the chemical reactions in the body and regulate every living process (see p18). Antibodies, and many other crucial components of the immune system, are also proteins.
Proteins can do these many different jobs because they are made up of long chains of chemicals called amino acids. The types of amino acid present, and the order in which they occur, is different for each type of protein. Once the chains have been formed.
they are folded up in a specific way to give a compact protein molecule, often spherical or sausage-shaped. In the case of enzymes, one small area on the surface of the molecule is the active site, where the crucial chemical reaction controlled by that enzyme occurs. Similarly, in antibodies, the particular combination and arrangement of amino acids at the antigen-binding site decides which antigen it will bind.
There are 20 common types of amino acid each with its own distinctive chemical properties. Some are attracted to water, others repel it. Some can react with one type of molecule, others do not. It is the different combinations of amino acids that make proteins so different from one another. They give enzymes their impressive range of chemical abilities, and account for the versatility of antibodies.
*28\180\8*
Random Posts
Leave a Reply
You must be logged in to post a comment.