Myoglobin hydrophobic cavities

The most characteristic amino acid residue of the distal side is again the residue closest to the iron, the distal histidine (Figure 2). The globular structure of myoglobin is characteristic for all the globins and excludes the formation of large cavities in the protein interior. Since this is a mainly hydrophobic region very few structural water molecules were located inside the protein. Polar... 

---