Biosynthetic Inorganic Chemistry
Potential Tuning
Heteronuclear Metalloenzymes
Unnatural Amino Acids and Non-Native Cofactors

We are interested in synthesis of inorganic catalysts that structurally and functionally mimic native metalloenzymes. Instead of using small organic molecules as ligands, we use small, stable and well-characterized proteins as ligands. This biosynthetic approach has many advantages. Thanks to recent advances in biology, we can synthesize protein ligands more easily, much faster and in higher yields than many complex organic ligands, and the resulting model metalloproteins can be studied under the same physiological conditions as native enzymes. More importantly, the protein ligands are much more rigid and allow investigation of the roles of non-covalent interactions in the secondary coordination sphere in controlling the activity of the metal centers, resulting in catalysis with much higher activity than most biomimetic compounds.

Using this biosynthetic approach, we focus on designing environmentally benign catalysts with applications in renewable energy generation and small molecule activation or transformation. For example, we are interested in designing metalloproteins with tunable redox potentials and in studying their applications in many chemical and biological processes from efficient electron transfer (ET) agents in photosynthesis and respiration to catalysis in water oxidation and N2 fixation. In addition, we have designed biosynthetic models of heteronuclear metalloenzymes such as heme-copper oxidases (HCOs), efficient oxygen reduction enzymes, nitric oxide reductases (NORs), which are involved in the nitrogen cycle, sulfite reductase, which is involved in sulfur cycle, and manganese peroxidases, which are involved in biomass conversion. Finally, we are introducing unnatural amino acids and non-native cofactors, including many inorganic and organometallic catalysts, to make them water-soluble, asymmetric catalysts for applications such as synthesizing chiral intermediates in pharmaceutical drugs.

For in-depth reviews of our research, please see our recent publications in
Curr. Opin. Chem. Biol, BBA-Bioenergetics, Nature, Inorganic Chemistry, and Angewandte Chemie

A presentation by Dr. Lu about the details of our process may also be viewed below.
(Click Title to View the Presentation)