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Question
Proteins are found to have two different types of secondary structures viz. α-helix and β-pleated sheet structure. α-helix structure of protein is stabilised by:
Options
Peptide bonds
van der Waals forces
Hydrogen bonds
Dipole-dipole interactions
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Solution
Hydrogen bonds
Explanation:
These structures arise due to the regular folding of the backbone of the polypeptide chain due to hydrogen bonding between > C – O and N – H – group of the peptide bond.
α-helix is one of the most common ways in which a polypeptide chain forms all possible hydrogen bonds by twisting into a right-handed screw (helix) with the –NH group of each amino acid residue hydrogen-bonded to > C = O of an adjacent turn of helix.
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