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Expert has expertise in the purification and characterization of disulfide-containing redox proteins from a variety of micro-organisms. She has used the standard techniques of both low and high pressure chromatography on ion exchange and size exclusion gels. She is also familiar with affinity and immunochemical techniques. She is proficient with molecular biology procedures to isolate and clone genes and overproduce proteins of interest for both physical characterization and sequencing.

In her work, Expert routinely uses various types of chromatography including ion exchange, size exclusion, affinity, and hydrophobic variants and HPLC for purification. Protein characterization is done by gel electrophoresis, UV-visible spectroscopy, and fluorescence. She has done both steady-state and rapid kinetics to correlate enzyme structure with function.

Expert and her colleagues are interested in producing mutant proteins by random and site-directed mutagenesis. They have used both kinetic data and molecular modeling to try and predict the effects of amino acid substitutions on structure.

Several years ago, Expert initiated a project on the isolation and purification of an herbicidal natural product from the blue-green alga, Scytonema hofmanni. She and her colleagues were able to characterize the compound using mass and infrared measurements.

Expert has an active program in collaboration with another faculty member to isolate and identify natural products from freshwater algae and plants. Her current work is on anti-algal compounds and an insect attractant produced by Eurasian water milfoil. Bioassays are set up with the appropriate test organisms and standard techniques are used to extract small, active molecules from plant materials such as thin-layer and high-pressure chromatography.

Expert has been investigating the mechanism of action for a disulfide-containing redox protein called thioredoxin for several years. In collaboration with colleagues at the University of Arizona, she has used both steady-state and stopped-flow techniques to monitor interactions of thioredoxin with other proteins and to measure rates of electron transfer. These kinetic analyses have been coupled with protein engineering to identify amino acid residues in the protein which are critical for activity.