Question

Which of the following is not correct about the stabilizing Forces?

(a) Protein structures from secondary to quaternary are maintained by noncovalent forces

(b) They include electrostatic interactions but not van der Waals forces, and hydrogen bonding

(c) Electrostatic interactions are a significant stabilizing force in a protein structure

(d) Electrostatic interactions occur when excess negative charges in one region are neutralized by positive charges in another region

The question was posed to me in a national level competition.

This intriguing question originated from Protein Structure Basics in portion Structural Bioinformatics of Bioinformatics

Answer 1

Right option is (b) They include electrostatic interactions but not van der Waals forces, and hydrogen bonding

To explain I would say: It includes electrostatic interactions, van der Waals forces, and hydrogen bonding. The result is the formation of salt bridges between oppositely charged residues. The electrostatic interactions can function within a relatively long range (15 Å). Hydrogen bonds are a particular type of electrostatic interactions similar to dipole–dipole interactions involving hydrogen from one residue and oxygen from another. Hydrogen bonds can occur between main chain atoms as well as side chain atoms.