Thr and/or Leu residues tend to disrupt an $\alpha$ helix when they occur next to each other in a protein because:
A) an amino acids like Thr is highly hydrophobic.
B) covalent interactions may occur between the Thr side chains.
C) electrostatic repulsion occurs between the Thr side chains.
D) steric hindrance occurs between the bulky Thr side chains.
E) the R group of Thr can form a hydrogen bond.

Question

Quizplus · Accepted Answer

Thr and Leu residues are both large and bulky, so when they occur next to each other, steric hindrance can occur, disrupting the helix. Hydrophobicity, covalent interactions, and hydrogen bonding do not explain the disruption of the helix, and electrostatic repulsion would only occur with charged amino acids.

Thr And/or Leu Residues Tend to Disrupt An α\alphaα Helix When They Occur Next to Each Other in a When

Thr And/or Leu Residues Tend to Disrupt An $\alpha$ Helix When They Occur Next to Each Other in a When