Theoretical Study on the Effects of Environment around the Active Site on Ionization Potential in [2Fe-2S] Ferredoxin

Abstract

Iron–Sulfur clusters are often found in active sites of electron–transfer proteins. Their redox potentials are well controlled; however, its mechanism has not been understood well. In this study, therefore, we elucidate the effects of the protein-field, especially hydrogen bonds around the active site on the redox potential by using density functional theory (DFT) calculations. The results indicate that the ionization potentials are in proportion to the number of hydrogen bonds around the active site.