Converting CooA from a Carbon Monoxide to an Oxygen-Sensing Heme Protein Transcription Factor: Investigations into the Structure and Mechanism of Gas Binding

CooA is a carbon monoxide-sensing (CO-sensing) heme protein transcription factor that regulates gene activation in several bacteria and, importantly, is a convenient model for studying analogous proteins in the human body. In the present study, the specificity and mechanism of gas-binding of CooA have been investigated by efforts to convert CooA from a CO to an oxygen (O2) sensor through site directed mutagenesis of residues in the gas binding pocket of the heme group. The resulting mutated proteins were then isolated and characterized with spectroscopy. The results of this research project will provide further insight into the current model for the specificity and mechanisms of gas binding in heme proteins