Spectroscopic Analysis of Nitric Oxide Synthase: Effects of Solvent Composition on the Heme Pocket
Goode, Whitney E.
MetadataShow full item record
Nitric oxide (-NO) is an important biomolecule involved in many normal cellular functions, including regulation of blood pressure, and in several pathogenic states including Alzheimer's Disease. -NO produced selectively by three distinct isoforms of the enzyme nitric oxide synthase (NOS) performs specific functions. Regulation of -NO is therefore paramount. Selective inhibition of NOS is difficult because the active sites are very similar. The recently solved crystal structures of the active sites of NOS demonstrate subtle differences that could be exploited in designing selective isoform inhibitors. Spectroscopic analysis of NOS in either 10% Aceotonitrile (0.05% TFA in 100mM HEPES, pH7.4) [organic] or in an aqueous solution (lOOmM HEPES, pH 7.4) was done. Results demonstrate that solvent content effects differentially the heme Soret (found in the active site) of NOS isoforms. These results suggest that NOSs have different chemical composition in their active sites that could be exploited in drug design.