... structure of the h aem iron and redox-dependentcatalytic control of the PDE domain. In this report, wediscuss the mechanism of catalytic control o f Ec DOS,based on the physico-chemical characteristics ... significant changes i n t he redox potentialof the haem, rate constants o f CO, O2and CN b inding tohaem, and CD spectra in the Soret region [15–18],suggesting that this residue is critical for ... aerobic condi-tions on Shimadzu UV-1650, UV-2500 and Hitachi U-2010spectrophotometers maintained at 25 °C using a tempera-ture controller [2,3,15,17,18]. Anaerobic spectral experi-ments were conducted...