Swappin' Sidechains. As in Intro to Design, two sidechains can be mutated. This time, pick a large hydrophobic amino acid to fill the voids.
This puzzle is similar to Intro to Design, but this time, the problem is voids, not clashes. Again, two segments can be mutated to a different amino acid.
Mutate wheel menu. Amino acids in the outer ring are hydrophobic, and the ones in the inner ring are hydrophilic.
Madde's "Swappin' Side Chains" video
Loci's "Swappin' Side Chains" video
Select Design Mode, then click on one of the light-colored segments. Select one of the large hydrophobic amino acids from the orange outer ring of the mutate wheel. (Cheat: tryptophan (TRP or W) is the largest sidechain out there.)
As in the previous puzzle, wiggle is not available, but shake is. Try some different mutations, and see what impact they have on the voids and the score.
