A peptide bond is a covalent bond that connects amino acids in a protein chain.

Peptide bonds are formed via a condensation reaction between the carboxyl group ($-COOH$) of one amino acid and the amino group ($-NH_2$) of another amino acid. During this reaction, a molecule of water is released, resulting in the formation of a peptide bond between the two amino acids.

The synthesis of a peptide bond requires energy, which is provided by adenosine triphosphate (ATP). This process is facilitated by ribosomes, which are enzyme complexes located in the cytoplasm of cells. Ribosomes interpret the genetic code present in messenger RNA (mRNA) and utilize this information to assemble amino acids into a protein chain.

Peptide bonds play a crucial role in both the structure and function of proteins. They establish a linear backbone that influences the protein’s shape and contribute to its chemical properties. The specific sequence of amino acids in a protein chain is dictated by the genetic code, and any alterations to this sequence can significantly impact the protein’s function.

In summary, a peptide bond is a covalent link between amino acids in a protein chain, formed through a condensation reaction between the carboxyl group of one amino acid and the amino group of another. This process, catalyzed by ribosomes, is essential for protein structure and function. Moreover, any changes to the amino acid sequence can have profound effects on the protein’s functionality.