Principles of protein–protein recognition

Abstract
The formation of the protein–protein interface by the insulin dimer, the trypsin-PTI complex and the αβ oxyhaemoghbin dimer removes 1,130–1,720 Å2 of accessible surface from contact with water. The residues forming the interface are close packed: each occupies the same volume as it does in crystals of amino acids. These results indicate that hydrophobicity is the major factor stabilising protein–protein association, while complementarity plays a selective role in deciding which proteins may associate.