Calculation of the circular dichroism spectra of carbon monoxy- and deoxy myoglobin: interpretation of a time-resolved circular dichroism experiment.
A calculation of the circular dichroism (CD) spectra of carbon monoxy- and deoxy myoglobin is carried out in relation with a time-resolved CD experiment. The calculation is based on the polarizability theory and the parameters are adjusted to fit the experimental absorption and CD spectra. By performing the calculation for intermediate configurations of the protein, we are able to propose an explanation of the CD structure observed on a sub-100 ps time scale. The role of the proximal histidine is, in particular, clearly demonstrated in the first step of the myoglobin relaxation from its liganded to it deliganded form.
Dartigalongue
Thibault
T
Laboratoire d'Optique et Biosciences-Centre National de la Recherche Scientifique-Institute National de la Sante et de la Recherche Medicale, Ecole Polytechnique, 91128 Palaiseau Cedex, France.
Hache
François
F
D000042:Absorption; D000465:Algorithms; D000818:Animals; D001703:Biophysics / Q000379:methods; D002244:Carbon / Q000737:chemistry*; D002627:Chemistry, Physical / Q000379:methods; D002942:Circular Dichroism; D006639:Histidine / Q000737:chemistry; D008024:Ligands; D008956:Models, Chemical; D015233:Models, Statistical; D008968:Molecular Conformation; D009211:Myoglobin / Q000737:chemistry*; D013059:Spectrum Analysis, Raman
D008024:Ligands; D009211:Myoglobin; C055547:deoxymyoglobin; D006639:Histidine; D002244:Carbon