Page 115 - General Biochemistry

• Alcohol containing
• Imine
• Aromatic
• Organic acid

1) Aliphatic amino acids
Ex: glycine, alanine, valine, leucine, isoleucine
2) Imino amino acid
The only secondary (2°) amino acid or (“imino” acid.) is proline where, the

nitrogen atom is attached to the α-carbon by a chain of three other carbon
atoms
3) Aromatic amino acids
Ex: phenylalanine, tyrosine, tryptophan

4) Alcohols
Ex: serine, threonine
5) Sulfur containing amino acids
Ex: cysteine, methionine
6) Acids and related amides
Ex: aspartate, glutamate, asparagine, glutamine
7) Basic amino acids
Ex: lysine, arginine, histidine
Classification of amino acids on basis of nutrition

1) Essential amino acids : they are amino acids that cannot be made by the
body and should be obtained from food
They are: isoleucine, leucine, lysine, methionine, phenylalanine, threonine,
tryptophan, valine, arginine, and histidine.
All aromatic amino acids are probably essential

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