MCQ
The helical structure of protein is stabilised by
  • A
    Depeptide bond
  • Hydrogen bond
  • C
    Ether bond
  • D
    Ester bond

Answer

Correct option: B.
Hydrogen bond
b
The helical structure of proteins is stabilized by hydrogen bonds. In helical structure, the carbonyl oxygen atoms in $C = O$ points in one direction, towards the amide hydrogen atoms in $NH$ groups,$4$ residues away. Together these groups form a hydrogen bond, one of the main forces of secondary structure stabilization in proteins. Hydrogen bonds are shown by dashed lines.

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