Write a short note on peptide bond.

Explanation

(i) The amino acids are linked covalently by peptide bonds.
(ii) The carboxyl group of the first amino acid react with the amino group of the second amino acid to give an amide linkage between these amino acids.
(iii) This amide linkage is called peptide bond. The resulting compound is called a dipeptide.
(iv) Addition of another amino acid this dipeptide by a second peptide bond results in tripeptide.
( v) When number of amino acids are linked there is a formation of polypeptide.
(vi) If formation of the number of amino acids are less it is called as a polypeptide, if it has large number of amino acids (and preferably has a function) then it is called a protein.
`H_(2)N-CH_(2)-COOH+H_(2)N-underset(CH_3)underset(|)"CH"-COOH underset(-H_2O)rarr`