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JEE Main · 2021 · 24 Feb 2021 · Shift 1 · Biomolecules

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Out of the following, which type of interaction is responsible for the stabilisation -helix structure of proteins ?
  1. (A)Ionic bonding
  2. (B)Hydrogen bonding✓ Correct
  3. (C)vander Waals forces
  4. (D)Covalent bonding

Answer: (B)

Solution

The -helix is a secondary structure of proteins characterized by a right-handed coiled conformation. This structure is stabilized by intramolecular hydrogen bonds between the carbonyl oxygen (C=O) of one amino acid residue and the amide hydrogen (N-H) of another amino acid residue located four residues ahead in the sequence. These regular hydrogen bonds along the backbone of the polypeptide chain maintain the helical structure. Therefore, hydrogen bonding is responsible for the stabilization of the -helix structure.

JEE Main · 2021 · 24 Feb 2021 · Shift 1 · Single correct option

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