Peptidbindungen

Amino acids covalently bond to each other through peptide bonds. A peptide bond links the carboxyl group of one amino acid to the amino group of the other. Peptides are small chains of amino acids ranging from two to fifty monomers.

A peptide bond forms through a condensation reaction that releases a water molecule. When an amino group and a carboxyl group link together, it results in the formation of an amide group. The peptide bond has a rigid planar structure and shows some characteristics of a double bond. This is because the double bond on the carbonyl can act as a resonance structure with the carbon-nitrogen peptide bond. 

This resonance leads to the decrease in the length of the single bond, an increase in the length of the double bond, and inhibits rotation of the groups around the peptide bond.

Peptide bonds can exist in cis and trans conformations. In the cis conformation, the alpha carbons are on the same side of the peptide bond, and in the trans conformation, they are on opposite sides of the bond. Peptide bonds mostly occur in the trans conformation except when proline contributes its amino group to bond formation.

Amino acids linked through peptide bonds have an N-te