Final answer:
Tertiary structures in proteins are stabilized by ionic bonding, disulfide linkages, dispersion forces, hydrophobic interactions, and other weak forces such as salt bridges and coordinate bonds with metal ions, in addition to hydrogen bonds.
Step-by-step explanation:
Apart from hydrogen bonding, multiple forces contribute to stabilizing the tertiary structure of proteins. One of these is ionic bonding, which occurs between positively and negatively charged side chains of amino acids. Another important interaction is the creation of disulfide linkages, also known as disulfide bonds, which are covalent bonds that form between the sulfur atoms of two cysteine amino acids. Lastly, dispersion forces, weak interactions that occur between nonpolar side chains, also play a role in stabilizing the tertiary structure.
Beyond these, the presence of hydrophobic interactions greatly influence protein folding. These occur when nonpolar, water-fearing side chains cluster away from the aqueous environment, stabilizing the interior of the protein. Salt bridges, coordinate bonds with metal ions, and other weak interactions such as van der Waals forces may also contribute to the overall stability of the protein's tertiary structure.