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Proteins, the basics

How to make a designer drug

In the early 1900s Emil Fischer discovered that protein structures consist of amino acids. This lead to the science known as peptide chemistry.

The process starts with amino acids, the building blocks of life. Amino acids are made of carbon, hydrogen, oxygen, nitrogen and in some cases sulphur. There are 22 known amino acids, of which 8 cannot be manufactured by the body and must be consumed in adequate amounts for optimum nutrition and health. Twenty amino acids combine, using a peptide bond, to form peptides. (A peptide is basically a short protein.)

The specific order amino acids combined affects the structure and properties of the protein; some are rigid, some flexible. When a protein is large enough it may “fold” into ribbons or corrugated sheets.

Proteins are found in each living cell of every animal including humans. They have a wide range of functions. Some form keratin, a key ingredient in hair, skin, fingernails and bone. There is protein in muscles, too.

Enzymes are proteins that expedite chemical changes in tissue or organs; other proteins act as hormones regulating metabolism; and some carry oxygen throughout the body.

Some proteins are also antibodies that fight dangerous viruses and bacteria. In pemphigus and pemphigoid certain antibodies (called autoantibodies) get confused and attack the desmogleins that hold cells together; the result is lesions. Prednisone is used to suppress many different antibodies because there’s been no way to detect and stop only the ones doing the damage. This principle is true of most autoimmune diseases like arthritis, lupus and multiple sclerosis.

When prednisone is taken it circulates in the blood throughout the entire body. This is very inefficient and encourages harmful side effects as the drug interacts with healthy tissues and organs.

Today scientists can link amino acids together to form “designer” peptides and in turn, link peptides to form proteins. Scientists around the world are looking for molecules, amino acids, peptides or proteins that can be spliced into, or attached to other amino acids, peptides or proteins that can repair, replace or neutralize harmful genes or other substances that cause disease. Some are even “programed” to go exactly where they are needed, to the specific cells that break down to cause disease. By creating peptides and proteins with specific properties, researchers can construct much more effective medicines for any number of diseases.

The process is relatively new, and there is much more that needs to be done to identify and manipulate the properties of peptides. Peptimmune is one of the companies in this exploding field of science. This means more effective treatments and less unpleasant side effects.