PEPTIDE FORMATION AND PROTEINS

Proteins are the largest and most complicated molecules that exist in the cells of living organisms. 

Proteins are polymers that are formed by many hundreds or even thousands of amino acid units. These units are bonded together by a peptide linkage. 

Peptides are amides formed by the reaction of amino groups with the carboxyl groups of amino acids. According to the number of amino acid units they are made up from, they are known as dipeptides, tripeptides or polypeptides. 

If the number of amino acids forming polypeptide bonds is more than 12.000, the polypeptides are called PROTEINS. 

Although proteins contain only 20 kinds of amino acids, they can be arranged in many different sequences. Consequently, a small number of amino acids may form many different types of proteins. 

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