The goals of this research project are to apply electrochemical techniques to the study of the Co corrinoid compounds in vitro in order to understand the activation of the Co-C bond in enzymatic reactions. One of our long term objectives has been the study of the redox chemistry of vitamin B12 species with a view toward understanding their involvement in biochemical processes. With this goal in mind, we plan to study two mechanistic schemes: (i) the reductive cleavage of organo-B12 species and (ii) B12 catalyzed reduction reactions. The first project, (i) will be a study of the reduction process of alkylcobalamins, alkylcobinamides, and model systems using electrochemical techniques in order to understand in detail the reductive cleavage mechanism in which the carbon-cobalt bond is cleaved by an electron transfer reaction.
Our aim i s to obtain information on how substituent group structure affects (a) the reduction potentials of organo-B12 species and (b) the rate constants for electron transfer and for Co-C bond fission. These results could help in understanding how the Co-C bond is activated in enzymatic reactions. In most cases, Co-C bond breaking is exceptional fast following an electron transfer event and electrochemical techniques for following such reactions in the musecond and nanosecond time domain have been developed to study these processes. Experiments to investigate the solvent, pH, and temperature dependence of the reaction steps are also necessary for a complete picture of the mechanisms. The second type electrochemical process to be investigated, (ii), is vitamin B12 catalyzed reductions, e.g., oxygen reduction for aerobic systems. This reaction requires the formation of a reduced vitamin B12 species, the Co(II), B12r, or the Co(I), B12s, which then can react rapidly with oxygen or other substrates. Here the rate and products of the process will be studied by voltammetry and spectroelectrochemistry at various electrodes. We also plan to use surface enhanced Raman spectroscopy (SERS) to elucidate the nature of B12 intermediates in these reactions.
|Fried, Eric S; Li, Yue-Ming; Gilchrist, M Lane (2017) Phase Composition Control in Microsphere-Supported Biomembrane Systems. Langmuir 33:3028-3039|
|Gilchrist, M Lane; Ahn, Kwangwook; Li, Yue-Ming (2016) Imaging and Functional Analysis of ?-Secretase and Substrate in a Proteolipobead System with an Activity-Based Probe. Anal Chem 88:1303-11|
|Fried, Eric S; Luchan, Joshua; Gilchrist, M Lane (2016) Biodegradable, Tethered Lipid Bilayer-Microsphere Systems with Membrane-Integrated ?-Helical Peptide Anchors. Langmuir 32:3470-5|
|Banerjee, Shaibal; Sinha, Saikat; Pradhan, Padmanava et al. (2016) Regiospecifically Fluorinated Polycyclic Aromatic Hydrocarbons via Julia-Kocienski Olefination and Oxidative Photocyclization. Effect of Fluorine Atom Substitution on Molecular Shape. J Org Chem 81:3983-93|
|Beck, Cade; Singh, Tanya; Farooqi, Angela et al. (2016) Controlled microfluidics to examine growth-factor induced migration of neural progenitors in the Drosophila visual system. J Neurosci Methods 262:32-40|
|Thomson, Paul F; Parrish, Damon; Pradhan, Padmanava et al. (2015) Modular, Metal-Catalyzed Cycloisomerization Approach to Angularly Fused Polycyclic Aromatic Hydrocarbons and Their Oxidized Derivatives. J Org Chem 80:7435-46|
|Salas-Ramirez, Kaliris Y; Bagnall, Ciara; Frias, Leslie et al. (2015) Doxorubicin and cyclophosphamide induce cognitive dysfunction and activate the ERK and AKT signaling pathways. Behav Brain Res 292:133-41|
|Small, Chiyedza; Ramroop, Johnny; Otazo, Maria et al. (2014) An unexpected link between notch signaling and ROS in restricting the differentiation of hematopoietic progenitors in Drosophila. Genetics 197:471-83|
|Zhong, Lina; Tu, Raymond; Gilchrist, M Lane (2013) Tether-supported biomembranes with ?-helical peptide-based anchoring constructs. Langmuir 29:299-307|
|Guleyupoglu, Berkan; Schestatsky, Pedro; Edwards, Dylan et al. (2013) Classification of methods in transcranial electrical stimulation (tES) and evolving strategy from historical approaches to contemporary innovations. J Neurosci Methods 219:297-311|
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