Perutz stereochemical mechanism

In the 30 years since the initial proposal, almost every aspect of Perutz s stereochemical mechanism for the cooperativity of binding oxygen has been challenged. But, as summarized by Perutz et al.,3 it has emerged virtually unscathed. Even the complex binding kinetics can be fitted to the simple two-state Monod-Wyman-Changeux mechanism.38... 

The original stereochemical mechanism of Perutz for the cooperative oxygenation of Hb suggests that the a chains should have a higher affinity for O2 than the p chains (Perutz, 1970). More recent high-resolution X-ray crystallographic results show that there are substantial differences between the distal portions of the a- and P-heme pockets in Hb A (Shaanan, 1983 Derewenda et al., 1990). 

Perutz MF, Wilkinson AJ, Paoli M, Dodson GG. The stereochemical mechanism of the cooperative effects in hemoglobin revisited. Annu. Rev. Biophys. Biomol. Struct. 1998 27 1-34. 

More recently Perutz (PIO) has proposed a stereochemical mechanism of heme-heme interaction which describes in detail the cooperative effects in hemoglobin. Most important in the oxygenation-deoxygenation... 

Based on the X-ray crystal structures of deoxy and ligated hemoglobins, Perutz formulated a molecular stereochemical mechanism for hemoglobin, a key tenet of which is a strained linkage... 

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