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Question
Define the following as related to proteins:
Peptide linkage
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Solution
Chemically, peptide linkage is an amide formed between the –COOH group and –NH2 group. The reaction between two molecules of similar or different amino acids proceeds through the combination of the amino group of one molecule with the carboxyl group of the other. This results in the elimination of a water molecule and the formation of a peptide bond –CO–NH–. The product of the reaction is called a dipeptide because it is made up of two amino acids.
For example, when the carboxyl group of glycine combines with the amino group of alanine, we get a dipeptide, glycylalanine.
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