• Linda Doerrer
• One of the outstanding mysteries in bioinorganic chemistry is the mechanism by which the {Mn₄Ca} water oxidizing complex (WOC) or oxygen evolving complex in photosystem II in plants functions.  Photosystem II is part of the photosynthetic process that brings visible light, CO₂, and water together to make carbohydrates and oxygen.  It is known that a cluster of four manganese atoms and one calcium atom is critical for this functioning, as well as the participation of a tyrosine residue from the protein environment.  The Doerrer Group is synthesizing first-row transition metal complexes with alkoxide anions, and they are interested in extending this chemistry to manganese to mimic WOC.  The REU Student will learn how to synthesize transition-metal complexes in the absence of H₂O and O₂ and characterize them.  Characterization techniques include NMR, UV-Vis, and IR spectroscopy, as well as solid state magnetism and single crystal X-ray diffraction.  Successful efforts in the first stages of the project could lead to more advanced work in the project such as reactivity studies.

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• Sean Elliott
• The research of the Elliott Group focuses on the electron transfer reactions found in nature that are mediated by proteins and enzymes. Such proteins include cytochromes c, a class of metalloprotein that contains heme iron, and iron-sulfur cluster proteins, where iron and sulfide are assembled into redox-active units. In either type of protein, these inorganic parts serve as molecular “wiring” for how a cell moves electronic equivalents, and they serve as enzymatic active sites. . Such enzymes are capable of multi-electron transfer reactions, and these types of chemistry incredibly important to the energy sciences. Further, our group specializes in the use of electrochemistry as a tool for assessing how these proteins and enzymes work.  Projects in our group focus on the structure-function relationship of biological electron transfer in model systems, encompassing many areas of biological chemistry. One example involves the study of ferredoxins, small redox-carriers that are essential for shuttling electrons across key steps of microbial CO₂ reduction. An REU student may design mutations of such a ferredoxin, to test how changes in the environment around the ferredoxin iron-sulfur cluster results in changes in redox chemistry. In other areas, our group develops strategies for deposition of enzymes at electrode surfaces, a potentially exploitable technology for biosensor development. In this area, an REU student will develop co-immobilization of multiple enzymes to develop a multi-enzyme cascade that allows for sensing analytes through direct and mediated voltammetry.

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