STRUCTURE OF DEOXY-QUATERNARY HEMOGLOBIN WITH LIGANDED BETA-SUBUNITS

[摘要] We have determined the structure of a T-state haemoglobin in which the heme groups of the .beta. subunits have carbon monoxide bound, and the .alpha. subunits have nickel replacing the haem iron and are ligand-free. The structural adjustments on binding ligand in the T state are in the same direction as those associated with the quaternary transition, and a translational shift of the haem is severely restricted. We explain how these observations may account for the low ligand affinity of the .beta. haem of T-state haemoglobin.

[发布日期] 1990-07-05