Abstract An excited state refers to the transient state that conveys energies greater than that of a state in equilibrium with surrounding media. Among various forms of excited states, electronically excited states are of significant importance because they are intimately […]
Abstract Artificial photosynthesis is the capture and conversion of light energy to drive the formation of fuels. In this talk, systems for artificial photosynthesis that incorporate biomolecular catalysts for the hydrogen evolution reaction will be presented. These systems are notable […]
Abstract Small-molecule activation is an important goal of catalysis research with broad implications for addressing humankind’s grand challenges associated with energy production and healthcare. Computational chemistry can aid in identifying key factors that enable chemically challenging small-molecule activation reactions. Using […]
Abstract Metalloenzymes and metallocofactors in nature often demonstrate uniquely high efficiency that cannot be observed elsewhere. One example is C-H bond activation by non-heme iron enzymes; mononuclear and binuclear iron sites can utilize O2 to form high-valent intermediates that abstract […]
Abstract Development of selective C−H oxidation catalysts under mild conditions is strongly desired because of the application for the synthesis of complicated organic compounds. A possible approach to this purpose is to mimic biological systems, because some enzymes are capable […]
Abstract Dioxygen is essential in life processes, and enzymes activate dioxygen to carry out a variety of biological reactions. One primary goal in biomimetic research is to elucidate structures of reactive intermediates and mechanistic details of dioxygen activation and oxygenation […]
Abstract The dioxygen activation at the catalytic sites of the enzymes occurs through several steps including the binding of O2 at a reduced metal center, the generation of metal-superoxo and -peroxo species, and the O-O bond cleavage of metal-hydroperoxo complexes […]
Abstract In the type 3 (T3) copper proteins of biological systems, the coupled dicopper active site reacts with O2 to form the peroxo intermediate species for O2 transportation and substrate oxygenation. In multicopper oxidases (MCO), the clustering tricopper active site […]
Abstract Tristetraprolin (TTP) uses three cysteine and one histidine residues to bind zinc ions. TTP regulates the expression of cytokines such as tumor necrosis factor α (TNF- α) by binding to AU-rich sequence elements (AREs) located at the 3’-untranslated region […]
Abstract Characterization of copper intermediates in enzymes and other catalysts that attack strong C-H bonds is important for unraveling oxidation catalysis mechanisms and, ultimately, designing new, more efficient catalytic systems. New insights into the nature of such intermediates may be […]