The primary structure of a protein is stabilized by
The primary structure of a protein is stabilized by
Select an option to attempt
Correct Answer: Option C
Explanation
Peptide bond in primary protein structure: The backbone of a polypeptide consists of-C-(O) repeat units connected by PEPTIDE BONDS (amide bonds). The peptide bond is a covalent bond (bond with partial double-bond character due to resonance, bond energy). The peptide bond is: planar (due to resonance); usually in trans configuration; resistant to hydrolysis under normal physiological conditions (very stable, half-life ~1000 years at neutral pH in the absence of enzymes). Denaturation (heat, urea, SDS, extremes of pH) disrupts H-bonds (secondary structure), hydrophobic interactions, and electrostatic bonds (tertiary/quaternary structure) but does NOT break peptide bonds (covalent). Therefore the primary structure is stabilised by covalent (peptide) bonds. Hydrogen bonds stabilise 2° structure; ionic bonds contribute to 3° structure.