What characterizes the tertiary structure of proteins?

The tertiary structure of proteins is characterized by the three-dimensional conformation that results from the folding of the polypeptide chain. This structure is crucial because it determines the overall shape of the protein, which is essential for its function. The folding process is guided by various interactions among the amino acid side chains, including hydrogen bonds, ionic bonds, hydrophobic interactions, and van der Waals forces.

The unique three-dimensional shape that emerges at this level of structure allows the protein to interact properly with other molecules, which is vital for its biological activity. Understanding the tertiary structure is fundamental in fields such as biochemistry and molecular biology, as it directly correlates with the protein's function in cellular processes.