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Sharpness (slower but prettier)   Background:

Hydrophobic pocket

The surface of hemoglobin is a recipe for disaster

The single change in sickle cell anemia might be inconsequential were it not for two other factors
1) The fact that hemoglobin exists at tremendously high concentration, making up about 1/3 of the mass of a red blood cell, and
2) The existence on the surface of hemoglobin of a place where a surface valine can fit and be sequestered from water.

Which of the candidate sites would make a good home for a protruding valine on the surface of a different hemoglobin tetramer?