George B. Richter-Addo
IRON MEDIATED CHEMICAL BIOLOGY OF NITROGEN OXIDES


Unexpected bending of NO in a heme thiolate derivative
Inorganic nitrogen oxides such as NO, nitrite, and hyponitrite play very important roles in biology. The chemistry of these nitrogen oxides (NOx) is directed by various iron-containing enzymes such as the muscle protein myoglobin, the blood protein hemoglobin, and the liver protein cytochrome P450. The health effects of some of these NOx species includes blood pressure control, cancer, and memory transmission. Importantly, all of these effects depend on the biocoordination chemistry of Fe.
Our research involves determining the role that Fe plays in directing the health related chemistry of NOx species such as nitric oxide (NO), nitrite, nitrosamines, nitrosothiols, and hyponitrite. We utilize a range of techniques including (i) inorganic syntheses of chemical and biological intermediates, (ii) advanced electrochemistry and fiber-optic infrared and optical spectroelectrochemistry for the determination of the redox behavior of heme models, (iii) molecular biology and mutagenesis to assess the effects of active site structure on protein function, (iv) structural biology using protein crystallography to determine three-dimensional structures of biomolecules, (v) vibrational and magnetic resonance spectroscopy, and (vi) density-functional theoretical calculations for the elucidation of the electronic structures of biological intermediates.
Research keywords:
biological inorganic chemistry; heme proteins; nitric oxide