What is a Dipeptide? | Formation, Structure & Examples

Biosynthesis

Biosynthesis occurs when a polypeptide is cleaved to produce a dipeptide through hydrolysis, with the help of the enzyme dipeptidyl peptidase. When proteins are digested to dipeptides and amino acids, the dipeptides are absorbed more rapidly than the amino acids. This is because their absorption involves a different mechanism. When the dipeptides are digested, they activate G-cells found in the stomach to secrete gastrin.

Dipeptide Example

A dipeptide is a molecule that consists of two amino acids joined together by a peptide bond. Some examples of dipeptides include carnosine, anserine, and homoanserine.

Carnosine

Carnosine is a dipeptide composed of a beta-alanine and a 3-methyl-L-histidine. Carnosine is commonly found in red meat. Additionally, it is a protein building block for our bodies. It is found in our muscles when they are at work, as well as, the heart and brain. There is some research on carnosine as a means to prevent aging because it interferes with chemicals that cause the aging process. Carnosine can also act as an antioxidant because it protects cells against oxidative damage.

Carnosine is a dipeptide composed of a beta-alanine and a 3-methyl-L-histidine. It is commonly found in red meat and in our body

Anserine

Anserine is a dipeptide composed of a beta-alanine and a methylhistidine. Anserine is commonly found in red meat and is an antioxidant. It comes from duck, turkey, chicken, salmon and tuna. It is a dietary dipeptide and is not found in human organs.

Anserine is a dipeptide composed of a beta-alanine and a methylhistidine. Carnosine is found in red meat and is an antioxidant.

Homoanserine

Homoanserine is a dipeptide composed of N-(4-aminobutyryl)-L-histidine. Homoanserine is found in the brain and muscles of mammals. It is a neuroactive dipeptide, which means it plays an important role in the regulation of pain by the brain.

Lesson Summary

A dipeptide is formed when two amino acids are joined together. A peptide bond links these amino acids together. A peptide bond is a covalent bond, formed as 2 amino acids are joined together through dehydration synthesis, a process in which a water molecule is removed as a byproduct to link monomers together. Dehydration synthesis, also referred to as polymerization, is an anabolic process in which a water molecule is removed to link monomers together to form a polymer. Amino acids consist of the amino (NH2) and carboxyl (COOH) functional groups. Peptide bonds form between the carboxyl group of amino acid 1, and amino group of amino acid 2. Water is removed as a byproduct. The resulting peptide bond is a C-N covalent bond that now links the two amino acids together, to form a dipeptide.

Dipeptides are produced through two methods: synthetic polypeptides and biosynthesis. Peptide synthesis occurs when two amino acids are coupled together by a peptide bond. Peptide bond formation occurs by a process called dehydration synthesis. Biosynthesis occurs when a polypeptide is cleaved to produce a dipeptide through hydrolysis, with the help of the enzyme dipeptidyl peptidase. Some examples of dipeptides include carnosine, anserine, and homoanserine. Dipeptides are organic compounds that help to maintain the pH of cells or act as antioxidants.