MYOGLOBIN CONCLUSIONS
1. Volume rendering based on excluded volumes offers a useful method to access the true amount of space available to CO after dissociation.

* Excluded volumes indicate three likely B sites: B1, B2 and the Heme pocket H

* The B1 site is consistent with the 31^o spectral polarization of CO, were as, the B2 and H sites are not consistent

* Potential B sites are surrounded by amino acids whose mutations cause large kinetic effects.
2. The CO frequency shifts may be interpreted in terms of the relative stabilization of three resonance structures:
(1) ⁺¹:C-:^-1 (red) (2) :C=: (red) (3) ^-1:C[equivalence]O:⁺¹ (blue)

* In the B1 and H sites the CO's carbon is in Van der Waals contact with electron rich Phe stabilizing structure (1) and causing a red shift

* Van der Waals contact in the B2 site with Ile 28 and Gly 25 indicates a blue shift.
3. Energy minimized carboxy myoglobin structures indicate the Fe-C-O bond takes on a linear tilted structure rather than a bent structure.
4. Molecular dynamic simulations of the A-state describe a constantly changing N-Fe-C-O dihedral angle. Two preferential conformations are detected with movement between conformations occuring at temperatures above 50K.