Lecturer: Prof. Yi Lu, Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
Location: DNL conference room on the first floor of Energy building No.1
Time: July 17, 2015 (Friday) 9:00 am
Introduction:
Dr. Yi Lu received his B.S. degree from Peking University in 1986, and Ph.D. degree from University of California at Los Angeles in 1992 under Professor Joan S. Valentine. After two years of postdoctoral research in Professor Harry B. Gray group at the California Institute of Technology, Dr. Lu started his own independent career in the Department of Chemistry at the University of Illinois at Urbana Champaign in 1994. He is now Jay and Ann Schenck Professor of Chemistry in the Departments of Chemistry, Biochemistry, Bioengineering and Materials Science and Engineering. He is also a member of the Center for Biophysics and Computational Biology, Beckman Institute for Advanced Science and Technology and Institute of Genomic Biology. His research interests lie at the interface between chemistry and biology. His group is developing new chemical approaches to provide deeper insight into biological systems. At the same time, they take advantage of recently developed biological tools to advance many areas in chemistry. Specific areas of current interests include a) design and engineering of functional metalloproteins as environmentally benign catalysis in renewable energy generation and pharmaceuticals; b) Fundamental understanding of DNAzymes and their applications in environmental monitoring, medical diagnostics, and targeted drug delivery; and c) Employing principles from biology for directed assembly of nanomaterials with controlled morphologies and its applications in imaging and medicine. Dr. Lu has received numerous research and teaching awards, including the Royal Society of Chemistry Applied Inorganic Chemistry Award (2015), Fellow of the Royal Society of Chemistry (FRSC, 2015), Fellow of the American Association for the Advancement of Science (2007), Early Career Award, Society of Biological Inorganic Chemistry (2007), Howard Hughes Medical Institute Professor Award (2002), Camile Dreyfus Teacher-Scholar Award (1999), Alfred P. Sloan Research Fellowship (1998), Research Corporation Cottrell Scholars Award (1997), and the Beckman Young Investigators Award (1996).Dr. Lu is also an inventor, with more than 20 US and international patents and an entrepreneur, as a co-founder of companies for environmental monitoring (www.ANDalyze.com) and medical diagnostics (www.GlucoSentient.com).
http://www.chemistry.illinois.edu/faculty/yi_lu.html
Abstract:
Metalloenzymes play critical roles in renewable energy, such as in photosynthesis, biofuel cells and water splitting or oxidation. Designing metalloenzymes is an ultimate test of our knowledge about metalloenzymes and can result in new biocatalysts for practical applications.1 In this presentation, we will provide three examples to demonstrate that, while reproducing the primary coordination sphere may be good enough to make structural models of metalloenzymes, careful design of the non-covalent secondary coordination sphere interactions is required to create functional metalloenzymes with high activity. In the first example, we demonstrate the fine-tuning of reduction potentials of azurin (Figure 1),2 a member of cupredoxin family that are involved in long-range electron transfers (ET) in many biological processes such as photosynthesis, to span ~1 V through carefully design of hydrophobicity and hydrogen bonding networks around the primary coordination sphere, and the use of these proteins to address fundamental questions in biological ET such as reorganization energy and Marcus inverted region.3 In the second example, we have shown that the roles of two conserved glutamate in converting myoglobin into nitric oxide reductase (NOR), one through binding to a non-heme iron (Figure 2)4 and the other through hydrogen bonding interaction.5 Such a model system allowed elucidation of reaction mechanism of NOR.6 Finally, we show that the presence of waters as part of new hydrogen-bonding network in myoglobin is necessary to confer oxidase activity in reducing O2 to water with minimum release of other reactive oxygen species and with > 1,000 turnovers.7 A combination of the above approach with rational tuning of redox potentials have recently resulted in new oxygen reduction reaction catalyst with a very low over-potential8 and activity approaching to that of native enzymes. Recent results and their implications for designing novel biocatalysts for alternative energies will be discussed.
References:
1. a) Y. Lu, et al., Nature 460, 855 (2009); b) I. D. Petrik, J. Liu, Y. Lu, Curr. Opin. Chem. Biol. 19, 67 (2014).
2. N. M. Marshall, et al., Nature 462, 113 (2009).
3. O. Farver, et al., Proc. Natl. Acad. Sci. 110, 10536 (2010).
4. N. Yeung, et al., Nature 462, 1079 (2009).
5. Y.-W. Lin, et al., Proc. Natl. Acad. Sci. 107, 8581 (2010).
6. S. Chakraborty, et al., Angew. Chem., Int. Ed. 53, 2417 (2014)
7. K. D. Miner, et al., Angew. Chem., Int. Ed. 51, 5589 (2012).
8. A. Bhagi et al., J. Am. Chem. Soc.136, 11882 (2014).
Contract: Guoqing Jia (9302)