Inorganic Chemistry Seminar: Professor Jonathan Rittle, University of California, Berkeley
Abut the Seminar
Discovery of Manganese-Dependent Monooxygenases
The aerobic oxidation of carbon–hydrogen (C–H) bonds in biology is currently known to be accomplished by a limited set of cofactors that largely include heme, nonheme iron, and copper. While manganese cofactors perform difficult oxidation reactions, including water oxidation within Photosystem II, they are generally not known to be used for C–H bond oxidation, and those that do catalyze this important reaction display highly limited intrinsic reactivity. In this seminar, I will describe a handful of homologous enzymes that either require manganese, iron, or mixtures thereof to functionalize strong, aliphatic C–H bonds (BDE = 100 kcal/mol). Structural and spectroscopic studies on these systems reveal redox-active, bimetallic active sites that represent the locus of O2 activation and substrate coordination. Our combined results dramatically expand the known reactivity of biological manganese–containing cofactors, and suggests that many uncharacterized (or mischaracterized) monooxygenases may similarly utilize manganese to perform crucial oxidative biochemical tasks.
About the Speaker
Jon received his Bachelor’s degree in Chemistry at Penn State where he worked with Michael Green on the study of transient intermediates in heme enzymes. He obtained a Ph.D at Caltech working with Jonas Peters on the synthesis of molecular iron catalysts operative for N2 activation. Following a postdoctoral stint with Akif Tezcan at UCSD centered on protein engineering, Jon began his independent career at UC Berkeley in 2018. His research program combines elements of inorganic chemistry, crystallography, biochemistry, spectroscopy (and a little bioinformatics) to elucidate and characterize reactive and/or unusual inorganic species involved in dioxygen- and C-H bond activation .