Peptide bonds, which link amino acids together to form peptides, are formed through a condensation reaction (also known as dehydration synthesis). This process joins amino acids via a covalent bond.
Here's a breakdown of the process:
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What are peptides? A peptide is a short chain of amino acids, typically ranging from 2 to 50 amino acids linked together. These peptides are the building blocks of proteins. [1]
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The Condensation Reaction:
- The carboxyl group (-COOH) of one amino acid reacts with the amino group (-NH2) of another amino acid.
- A molecule of water (H2O) is removed during this reaction, hence the term "condensation" or "dehydration synthesis."
- This removal of water results in the formation of a peptide bond (C-N) between the two amino acids.
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Peptide Bond Formation - Step by Step:
- Amino Acid Alignment: Two amino acids are positioned close to each other, facilitating the reaction between their carboxyl and amino groups.
- Water Removal: The oxygen atom from the carboxyl group and two hydrogen atoms (one from the amino group, one from the carboxyl group) combine to form a water molecule.
- Peptide Bond Creation: The remaining carbon atom from the first amino acid's carboxyl group forms a covalent bond with the nitrogen atom from the second amino acid's amino group, creating the peptide bond.
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The Result: This process creates a dipeptide (two amino acids linked together). The addition of more amino acids through the same condensation reaction process builds longer peptide chains and eventually proteins.
In summary, peptide bonds, the foundation of peptides and proteins, are formed by removing a water molecule between the carboxyl group of one amino acid and the amino group of another.
