Final answer:
The tertiary structure of proteins is formed and stabilized by hydrophobic interactions, ionic bonding, hydrogen bonding, disulfide linkages, and dispersion forces, which all contribute to the protein's three-dimensional shape and function.
Step-by-step explanation:
The tertiary structure of a protein is its three-dimensional shape, which is critical to its function. This structure is stabilized by five forces or interactions:
- Hydrophobic interactions, which occur when nonpolar amino acid side chains avoid contact with water and associate with each other.
- Ionic bonding, which takes place between positively and negatively charged side chains of amino acids.
- Hydrogen bonding, which involves bonds between polar amino acid side chains and water or other side chains.
- Disulfide linkages (disulfide bridges), which are strong covalent bonds that form between the sulfur atoms of two cysteine amino acids.
- Dispersion forces (or van der Waals forces), are weak attractions between all atoms regardless of polarity.
Together, these forces contribute to the unique shape and stability of the protein's tertiary structure.