Question

A folding domain of a polypeptide chain has a primary structure containing 5 phenylalanine residues as shown below, where F represents the side chain of phenylalanine.

F F F
_|____|____|_
| |
F F

If this domain folds in one of the two orientations below, which is more likely - the one on the left or the one on the right?
Would all the side chains be inside a circle or would they be outside a circle?
a. The one on the left
b. The one on the right

Answer 1

b. The one on the right

They will be inside the circle.

Step-by-step explanation:

Phenylalnine is an aromatic amino acid which is hydrophobic in nature.

It tends to get buried in the core of protein structure.

These phenylalanine residues isomerise to the favoured N and C terminus.

The phenylalanine residues will be inside the circle because they are hydrophobic in nature.

These residues will fold the one on the right, clockwise in the domain.