The R group or side chain of the amino acid serine is -CH₂-OH. The R group or side chain of the amino acid leucine is -CH₂-CH-(CH₃)₂. Where would you expect to find these amino acids in a globular protein in aqueous solution?
A) Serine would be in the interior, and leucine would be on the exterior of the globular protein.
B) Leucine would be in the interior, and serine would be on the exterior of the globular protein.
C) Both serine and leucine would be in the interior of the globular protein.
D) Both serine and leucine would be on the exterior of the globular protein.
E) Both serine and leucine would be in the interior and on the exterior of the globular protein.

Question

Quizplus · Accepted Answer

Leucine, with its hydrophobic side chain, would be more likely to be found in the interior of the globular protein where it can avoid contact with the aqueous environment. Serine, on the other hand, has a polar side chain with a hydroxyl group, making it more likely to be found on the exterior of the globular protein where it can interact with water molecules.

The R Group or Side Chain of the Amino Acid