Date of Graduation
Master of Science in Chemistry
nucleic acids, lanthanide fluorescence, tyrosinase, europium, enzyme kinetics
I am currently exploring the role of nucleic acid molecules in pre-arranging reactants in single-step enzymatic oxidation reactions. Recent work in has shown that the enzymatic oxidation of phenolic substrates that form part of an important clinical assay, can be significantly enhanced in the presence of nucleic acid sequences. My work focuses on investigation into the mechanistic role of the nucleic acid template molecules towards enzymatic reactions. I am working with a tyrosinase enzyme that catalyzes the intermolecular cyclization of L-DOPA in Dopachrome, which absorbs light at 475nm, in the presence of various DNA molecules. This research is important for insight into the fundamental processes underlying the templating activity. I have shown that the enzymatic reaction is affected both in the rate (KM) and how the enzyme binds to the substrate (Vmax). I am also exploring the use of lanthanide fluorescence to monitor aptamer-target interactions. Recent work has shown that there is an increase in fluorescence in the presence of quadruplex forming sequences. My work has shown through using the tyrosinamide aptamer, a proposed quadruplex forming aptamer, there is an increase in fluorescence at target concentrations as low as 500nM.
© Sarah Phillips
Phillips, Sarah, "Modulation of Enzyme Activity by DNA: a Kinetic Investigation of Enzyme Tyrosinase" (2011). MSU Graduate Theses. 1976.