Question

Salt bridges occur between ________.

• A. \( \text{Hydrophobic residues} \)
• B. \( \text{Charged residues} \)
• C. \( \text{Aromatic residues} \)
• D. \( \text{Backbone atoms} \)

Hint:

Salt bridges are often found buried deep within the protein core or at protein-protein interfaces to stabilize the structure.

Answer 1

The Correct Option is B

Concept: Protein stability is maintained by several types of non-covalent interactions.
• These include hydrogen bonds, van der Waals forces, and electrostatic interactions.
• A specific type of electrostatic interaction is known as a "Salt Bridge."

Step 1: The Chemistry of the Salt Bridge.
A salt bridge is a combination of two non-covalent interactions: hydrogen bonding and ionic bonding. It typically forms between the positively charged side chain of one amino acid and the negatively charged side chain of another.

Step 2: Identifying Participating Amino Acids.
Residues like Lysine or Arginine (positive) can form salt bridges with Glutamate or Aspartate (negative). Since these interactions require full or partial charges, they only occur between "Charged residues." These bridges are critical for the tertiary and quaternary structure of proteins. Final Answer: Salt bridges occur between Charged residues.