Faculty Recruiting Seminar - Kaipeng Hou

Enzymes catalyze complex transformations with remarkable efficiency and selectivity. A significant challenge in chemistry and biology has been the development of artificial systems that can effectively mimic the functions of these enzymes. First, I will discuss the synthesis of a metal–organic framework with site-isolated iron(II) centers in a coordination environment resembling the active site of taurine–α-ketoglutarate dioxygenase. This framework activates dioxygen at low temperatures to form high-spin iron(IV)=O species, which were characterized using various spectroscopic methods. In the presence of dioxygen, the framework is competent for catalytic oxygenation of cyclohexane and the stoichiometric conversion of ethane to ethanol. To further explore enzyme-like catalysis beyond porous materials, I will also discuss the de novo design of protein catalysts for nonbiological reactions. By carefully considering reaction mechanisms and protein biophysics, we successfully designed proteins incorporating synthetic porphyrins and hemes for asymmetric catalysis, achieving excellent enantiomeric ratios and total turnover numbers. These findings demonstrate that efficient de novo protein catalysts can be designed and hold great potential for a wide range of chemical processes.