peptide bond
Noun The primary covalent chemical bond that links amino acids together in a peptide or protein chain. It is formed between the carboxyl group (-COOH) of one amino acid and the amino group (-NH₂) of another, releasing a molecule of water (H₂O) in a condensation reaction. This bond is also known as an amide bond.
The term "peptide bond" is used specifically in the fields of biochemistry, molecular biology, and organic chemistry to describe the fundamental linkage in polypeptides and proteins. * The stability of a protein's structure depends on the sequence of amino acids connected by peptide bonds. * During protein synthesis, ribosomes catalyze the formation of peptide bonds between amino acids. * A peptide bond has a partial double-bond character, which restricts rotation and influences protein folding.
- Planarity of the peptide bond: The partial double-bond character makes the peptide bond planar, meaning the six atoms involved (the carbonyl carbon, oxygen, amide nitrogen, hydrogen, and the two adjacent alpha-carbons) lie in the same plane. This planarity is a key determinant of protein secondary structure.
- Cleavage of the peptide bond: This bond can be broken by hydrolysis, a reaction catalyzed by enzymes like proteases or peptidases, or by strong acids or bases in a laboratory setting.
- Amide bond: A more general chemical term for the functional group (-CO-NH-); a peptide bond is a specific type of amide bond found between amino acids.
- Peptide linkage: A synonymous term for peptide bond.
- Polypeptide: A chain of many amino acids linked by peptide bonds.
- Dipeptide: A molecule consisting of two amino acids joined by a single peptide bond.
- Amide bond (in the context of amino acids)
- Peptide linkage
- Peptide backbone: The repeating sequence of atoms (-N-Cα-C-) in a protein chain, from which the side chains extend. The "C" in this backbone is the carbonyl carbon of the peptide bond.
- Condensation reaction: The type of chemical reaction (dehydration synthesis) that forms a peptide bond, releasing a water molecule.
- Resonance hybrid: The peptide bond's partial double-bond character is explained by resonance between two possible structures, giving it increased stability and planarity.
- the primary linkage of all protein structures; the chemical bond between the carboxyl groups and amino groups that unites a peptide