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Dennis Dean

University Distinguished Professor
  • Department of Biochemistry
  • College of Agriculture and Life Sciences


Dr. Dean researches the biochemical-genetic analysis of the enzyme (nitrogenase) that changes nitrogen gas in the atmosphere into ammonia, as well as molecular mechanisms of metallocluster formation.


The three processes required to sustain life on earth include respiration, photosynthesis, and nitrogen fixation. All three of these involve oxidation and reduction reactions. For example, during respiration (breathing) food sources are oxidized to form carbon dioxide in a process that provides energy; during photosynthesis, plants use energy from the sun to reduce carbon dioxide to form sugars (food). These oxidation and reduction reactions occur at iron atoms that are found in complexes called iron-sulfur clusters. The biological formation of iron-sulfur clusters is different for different organisms. For this reason, and because formation of iron-sulfur clusters is required for an organism to survive, disruption of this process in pathogenic organisms provides an ideal target for the development of therapeutic agents. Furthermore, because photosynthesis and formation of nitrogenous fertilizers can be limited by the availability of iron-sulfur clusters, any improvement in iron-sulfur cluster formation by using genetic manipulation provides an avenue for increased food production and development of disease resistant crops.