The mechanism of oxygen sensing and signal transduction in the heme-based oxygen sensor protein HemAT from Bacillus subtilis

.................................................................................................................................25 Introduction ...........................................................................................................................26 Experimental Procedure .......................................................................................................29 Protein expression and purification ..................................................................................29 Sample preparation for measurements.............................................................................30 Spectrosc pic methods .......................................................................................................30 Results....................................................................................................................................32 Absorption spectra of the COand NO-bound HemAT-Bs ...............................................32 EPR spectra of the NO-bound HemAT-B .........................................................................33 Resonance Raman spectroscopy for the CO-bound HemAT-Bs........................................34 Resonance Raman spectroscopy for the NO-bound HemAT-B .......................................37 Discussion ..............................................................................................................................43 REFERENCES ......................................................................................................................46 Chapter 3: Signal transduction through the proximal heme pocket in HemAT-Bs upon ligand binding revealed by time-resolved resonance Raman spectroscopy .............................................. 49 Abstract..................................................................................................................................49 Introduction ...........................................................................................................................50 Experimental Procedure .......................................................................................................53.................................................................................................................................49 Introduction ...........................................................................................................................50 Experimental Procedure .......................................................................................................53