Biomedical Sciences; Biologically Inspired Chemistry & Physics; Energy, Catalysis & Green Chemistry; Structural Chemistry, Spectroscopy & Advanced Analysis; Inorganic & Organometallic; Physical Chemistry; Biochemistry & Biophysics.
Brandon received his B.S. in Chemistry at Washington State University in 2009 where he developed a profound interest in biochemistry and biophysics. He pursued a Ph.D. in Chemistry at Emory University studying abiotic-biotic interfaces for photocatalysis, the enzymatic mechanisms of hydrogenases, and proton-coupled electron transfer (PCET) dynamics at bioinorganic cofactors in the group of R. Brian Dyer. He then pursued postdoctoral studies at Harvard/Massachusetts Institute of Technology defining the targets of allosteric control and conformational gating that initiate long-range radical transfer during nucleotide metabolism by ribonucleotide reductase in the labs of Daniel G. Nocera (Harvard) and JoAnne Stubbe (MIT).
Organisms in all branches of the tree of life harness exotic cofactors, macromolecular dynamics, and elegant reaction design to enable obligatory chemical transformations that occur far from equilibrium. Research in the Greene lab seeks to elucidate the modalities of reaction control and specificity in enzymes that enable these reactions. We are explicitly interested in oxidation/reduction (redox) reactions that occur at potentials outside the conventional “biological window.” This window can be defined, to a first approximation, as the water solvent window, between water (H+) reduction to H2 and water oxidation to O2. Enzymatic catalysis outside this window must discriminate between a substrate of interest (typically pM-mM concentrations in vivo) and the surrounding solvent (~55 M). These enzymes often employ metal ions and/or open-shell intermediates, but are united by the requisite control of proton and electron dynamics. To interrogate how proton and electron control is achieved we apply a synergistic approach involving traditional and cutting-edge methods in protein engineering, molecular biology, spectroscopy, electrochemistry and structural analysis. This multi-facetted strategy allows us to both understand natural systems, and rationally design new ones for novel applications in bioenergy, biogeochemistry, and human health.
Greene, B. L., Stubbe, J., and Nocera, D. G. “Photochemical Rescue of a Conformationally Inactivated Ribonucleotide Reductase” J. Am. Chem. Soc. 2018, 140, 15744-15752.
Greene, B. L., Taguchi, A. T., Stubbe, J., and Nocera, D. G. “Conformationally Dynamic Radical Transfer within Ribonucleotide Reductase” J. Am. Chem. Soc. 2017, 140, 16657-16665.
Greene, B. L., Vansuch, G. E., Chica, B. C., Adams, M. W. W., and Dyer, R. B. “Applications of Photogating and Time Resolved Spectroscopy to Mechanistic Studies of Hydrogenases” Acc. Chem. Res. 2017, 50, 2718-2726.
Greene, B. L., Schut, G. J., Adams, M. W. W., and Dyer, R. B. “Pre-Steady-State Kinetics of Catalytic Intermediates of a [FeFe]-Hydrogenase” ACS Catal. 2017, 7, 2145-2150.
Greene, B. L., Vansuch, G. E., Wu, C. H., Adams, M. W. W., and Dyer, R. B. “Glutamate Gated Proton-coupled Electron Transfer Activity in a [NiFe]-Hydrogenase” J. Am. Chem. Soc. 2016, 138, 13013-13021.
Greene, B. L., Wu, C. H., Vansuch, G. E., Adams, M. W. W., and Dyer, R. B. “Proton Inventory and Dynamics in the Nia-S to Nia-C Transition of a [NiFe]-Hydrogenase” Biochemistry 2016, 55, 1813-1825.
Greene, B. L., Wu, C. H., McTernan, P. M., Adams, M. W. W., and Dyer, R. B. “Proton-coupled Electron Transfer Dynamics in the Catalytic Mechanism of a [NiFe]-Hydrogenase” J. Am. Chem. Soc. 2015, 137, 4558-4566.
Greene, B. L., Joseph, C. A., Maroney, M. J., and Dyer, R. B. “Direct Evidence of Active-site Reduction and Photodriven Catalysis in Sensitized Hydrogenase Assemblies” J. Am. Chem. Soc. 2012, 134, 11108-11111.