Imaging protein statistical substate occupancy in a spectrum-function phase space.
Hemeprotein ligand rebinding studies reveal varying IR absorbance and rebinding functions across a cryogenic ensemble. Since IR-active vibrations and rebinding barriers couple to structural coordinates, spectral and functional heterogeneity arise from conformational heterogeneity. Modeling rebinding data as a spectrally resolved superposition of first-order rate processes and employing maximum entropy regularization, protein heterogeneity is imaged as an ensemble occupancy of a spectrum-function phase space. Results from myoglobin rebinding carbon monoxide are discussed.
DeWitt
W
W
Department of Physics, Cook Physical Sciences, University of Vermont, Burlington, Vermont 05405, USA.
Chu
K
K
D001665:Binding Sites; D002248:Carbon Monoxide / Q000737:chemistry* / Q000378:metabolism; D009211:Myoglobin / Q000737:chemistry* / Q000378:metabolism; D011487:Protein Conformation; D013055:Spectrophotometry, Infrared; D055672:Static Electricity; D013816:Thermodynamics; D014732:Vibration
D009211:Myoglobin; D002248:Carbon Monoxide