Concept 5 Review

The Peptide Bond

The peptide bond that binds amino acids is one of the strongest and most durable of covalent bonds.

Two amino acids can be joined together by dehydration condensation to form a dipeptide. In the laboratory, we can break, or hydrolyze, peptide bonds most effectively by a combination of heat and acid. In your body, this digestive process begins in the stomach, where a combination of acid and enzymes helps break peptide bonds.

Two amino acids joined to form a dipeptide

The figure above shows two amino acids being joined to form a dipeptide, splitting out water in the process (a dehydration condensation).

Below is a model of the dipeptide L-aspartyl-L-phenylalanine. A modified form of this dipeptide is known as aspartame.