Tertiary structure of proteins
The tertiary structure is the arrangement that the secondary structure adopts in space. Therefore, the primary structure determines which is the secondary and the tertiary structure.
This structure is maintained thanks to the bonds that occur between the -R radicals of the different amino acids, located at positions very far from the peptide chain.
- Hydrogen bridge bonds between nonionic polar groups in which there are partial charges in their side chain.
- Electrostatic attractions, ionic bonds between R groups of acidic amino acids (negatively charged, -COO-) and basic amino acids (positively charged, -NH3+).
- Hydrophobic attractions and Van der Waals forces between aliphatic radicals of apolar amino acid side chains.
- Disulfide bridges, covalent bonds between two thiol groups (-SH), corresponding to two cysteines.