Question

Which of the following forces stabilize the secondary structure of proteins? 
A. Hydrogen bonds
B. Covalent bonds
C. Disulphide linkages
D. Vander Waals forces

• A. A, B only
• B. A, C, D only
• C. A, D only
• D. B, C only

Hint:

The secondary structure of proteins is primarily stabilized by hydrogen bonding, along with disulfide bonds and Van der Waals interactions, while covalent bonds mainly contribute to primary structure stability.

Answer 1

The Correct Option is B

The secondary structure of proteins (such as \(\alpha\)-helices and \(\beta\)-pleated sheets) is stabilized mainly by non-covalent interactions, specifically:

1. Hydrogen Bonds (A): These occur between the carbonyl oxygen of one amino acid and the amide hydrogen of another, stabilizing \(\alpha\)-helices and \(\beta\)-sheets.
2. Disulfide Linkages (C): These are covalent bonds between cysteine residues that provide stability to protein structure.
3. Van der Waals Forces (D): These weak intermolecular forces help stabilize protein folding and secondary structures.

Covalent bonds (B) are not directly responsible for stabilizing the secondary structure of proteins; rather, they play a role in the primary structure.

Thus, the correct answer is A, C, D only.