Elementary plant Biochemistry and Biotechnology (2+1)

Amino acids

• All proteins are formed from 20 different amino acids. All the amino acids have trivial or common names based on the source from which they were first isolated or based on their properties. For eg. Asparagine was named so, as it was isolated from asparagus and glycine was so named because of its sweet taste (Greek:'glykos' meaning sweet). All the 20 amino acids, except proline, found in proteins have an amino group and a carboxyl group attached to the same carbon atom, namely the α-carbon . They differ only in the side chains (R groups). The 20 amino acids found in proteins are referred as the standard or normal or protein amino acids . There are many other amino acids found in nature but do not occur in proteins. They are referred as non-protein amino acids