Question

What is peptide linkage?

Hint:

A dipeptide contains two amino acids but only ONE peptide linkage. A tripeptide has three amino acids and TWO linkages.

Answer 1

Step 1: Understanding the Concept:
Proteins are polymers made of amino acids. The linkage that joins these amino acids together is the peptide bond or peptide linkage.
Step 2: Detailed Explanation:
A peptide linkage is an amide bond (\(-CO-NH-\)) formed by the condensation reaction between the carboxyl group (\(-COOH\)) of one amino acid and the amino group (\(-NH_2\)) of another amino acid, with the elimination of a water molecule.
\[ NH_2-R_1-COOH + NH_2-R_2-COOH \rightarrow NH_2-R_1-CONH-R_2-COOH + H_2O \]
Step 3: Final Answer:
The peptide linkage is the covalent bond \(-CO-NH-\) connecting amino acids in a polypeptide chain.