Protein Dynamic Studies of cytochrome cb562 Mutants
Authors:Nicole Bouley Ford, Dong Woo Shin
- Harry Gray, Arnold O. Beckman Professor of Chemistry, California Institute of Technology
- Jay Winkler, Faculty Associate in Chemistry, California Institute of Technology
Denatured proteins poses serious problems in biological systems, often acting as the pathogen in various diseases such as the BSE (“mad cow disease”) and CJD (Creutzfeldt–Jakob disease). By observing intermolecular diffusion in unfolded proteins, properties and characteristics of the denatured proteins can be understood in more detail. Using cytochrome cb562 mutants with a ruthenium photosensitizer in various locations, the method of contact quenching was used on proteins to measure the rate of contact formation between the photosensitizer and the iron heme. As the ruthenium photosensitizer comes into contact with the protein’s iron heme, the luminescence decay rate of the photosensitizer was observed using a nanosecond laser. From this study, decay rate of the photosensitizer was observed in varying GdmHCl concentrations and the distances of the photo sensitizer to the heme. This will shed light as to the nature of rigidity and the movements of the unfolded protein.