Three Dimensional Structure of Haemoglobin Rainier

The difference electron density map of deoxyhaemoglobin Rainier (α₂β₂^145Tyr→Cys) shows that the cysteine introduced by the mutation forms a disulphide bridge with the reactive cysteine, F9(93)β, of the same β-chain. The resulting structural distortions affect the C-terminus of the β-chain, thereby inhibiting part of the alkaline Bohr effect and haem–haem interaction.