报告题目：New-to-Nature Metalloredox Biocatalysis for Stereoselective Radical Transformations
报 告 人：Assistant Professor Yang Yang
University of California Santa Barbara
Bringing new catalytic functions to naturally occurring enzymes can dramatically expand the repertoire of enzymology and generate novel biocatalysts. Inspired by the innate redox properties of first-row transition-metal cofactor, our group has recently begun to repurpose metalloproteins to catalyze stereoselective radical reactions triggered by single electron transfer. Due to the lack of exploitable stereocontrol elements in synthetic systems, steering the absolute and relative stereochemistry of these free radical processes is notoriously difficult in asymmetric catalysis. We engineered a set of metalloenzymes to impose excellent stereocontrol over the bond forming events in these unnatural processes, allowing stereodivergent radical catalysis to be easily carried out. These metalloenzymes are fully genetically encoded and readily function in bacterial cells, displaying excellent activities at room temperature . Collectively, this evolvable metalloenzyme platform represents a promising solution to tame fleeting radical intermediates for asymmetric catalysis.
Dr. Yang Yang obtained a B.S. in Chemistry from Peking University where he did his undergraduate research with Prof. Jianbo Wang. During his undergraduate years, he also carried out summer research at the University of California, Los Angeles with Prof. Neil Garg. Yang received his Ph.D. degree in Organic Chemistry from the Massachusetts Institute of Technology under the guidance of Prof. Stephen Buchwald. At MIT, his research focused on copper-catalyzed asymmetric hydrofunctionalization of simple olefins. In particular, he developed an enantioselective hydroamination of unactivated internal olefins and a set of methods for the enantioselective addition of olefin-derived nucleophiles to carbonyls and imines. While in graduate school, Yang also spend a summer in the laboratory of Prof. Peng Liu at the University of Pittsburgh, where he used computational tools to elucidate the mechanism of copper-catalyzed olefin functionalization reactions. As an NIH Postdoctoral Fellow working with Prof. Frances Arnold at the California Institute of Technology, through directed evolution of cytochromes P450, Yang developed an enzymatic platform for the asymmetric amination of primary, secondary, and tertiary sp3 C-H bonds. By integrating organic chemistry, enzymology, protein engineering, computational modeling and inorganic spectroscopy, the Yang laboratory at the University of California Santa Barbara will address challenging problems in synthetic chemistry.