Three Dimensional Fourier Synthesis of Horse Deoxyhaemoglobin at 2.8 Å Resolution

THE deoxyhaemoglobin of horse forms orthorhombic crystals with the space group C222₁ and four molecules in the unit cell, which lie on two-fold symmetry axes. A Fourier synthesis at 5.5 Å resolution showed the tertiary structures of the individual subunits to be closely similar to that of oxyhaemoglobin, but the quaternary structure of the tetramer to be markedly different^1,2.