Plovdiv Entrance Practice Test

A peptide bond is an amide linkage formed when the carboxyl group of one amino acid reacts with the amino group of another amino acid. In this dehydration synthesis, the carbonyl carbon of the carboxyl group is joined to the nitrogen of the amino group, releasing a molecule of water. The result is a C–N bond that links two amino acids into a dipeptide, and this same connection repeats to build longer polypeptides in proteins. The key functional groups involved are the carboxyl group and the amino group.