Proteinogenic amino acids are 20 amino acids, which differ in that they are encoded by a genetic code, and are included in the process of translation into proteins . They are classified based on the structure and polarity of their side chains.
Properties of proteinogenic amino acids
The properties of such amino acids depend on their class. And they are classified by many parameters, among which you can list:
- by the radical (charged "+" and "-", polar uncharged, nonpolar);
- by functional groups (sulfur-containing amino acids, aliphatic, aromatic, imino acids and heterocyclic compounds);
- by the nature of catabolism (ketogenic amino acids, glycogen, and compounds of a mixed type);
- by chemical properties (monobasic, acidic, dicarboxylic amino acids);
- by origin (amines, natural amino acids obtained artificially).
Each class has its own characteristic.
Classification of proteinogenic amino acids
There are seven classes of such amino acids (they can be seen in the table). Consider them in order:
- Aliphatic amino acids. This group includes alanine, valine, glycine, leucine and isoleucine.
- Sulfur-containing amino acids. This species includes acids such as methionine and cysteine.
- Aromatic amino acids. This group includes phenylalanine, histidine, tyrosine, and tryptophan.
- Neutral amino acids. This category includes serine, threonine, asparagine, proline, glutamine.
- Imino acids. Proline, the only element in this group, it is more correct to call it an amino acid rather than an amino acid.
- Acidic amino acids . Aspartic and glutamic acids are included in this category.
- Basic amino acids. This category includes lysine, histidine and arginine.