❶ Antifreeze proteins
Antifreeze proteins are found in a wide range of cold adapted organisms, and they contribute to their freeze resistance. Antifreeze proteins adsorb to the ice surface and inhibit the growth of ice crystals. The goal of this project is to investigate the mechanism by which antifreeze proteins protect against the damage typically inflicted by cold, including the underlying molecular mechanism of ice-binding. Current efforts focus on the development of bioinspired protein-polymer antifreeze materials. This is a collaborative project with Dr. John Tsavalas (University of New Hamsphire), Dr. Paul Baures (Florida State University Panama City), and Dr. Emily Asenath-Smith (Cold Regions Research and Engineering Laboratory, Hanover, NH). We acknowledge support from NASA-EPSCoR and NIH.
Representative publication: Intracellular and extracellular antifreeze protein significantly improves mammalian cell cryopreservation. Biomolecules (2022) 12: 669.
❷ Bacterial mechanisms for establishing and maintaining cell polarity
The objective is to use structure-function analysis to understand bacterial mechanisms for establishing and maintaining cell polarity. This is a collaborative project with Dr. Grant Bowman (University of Wyoming). We acknowledge support from NIH.
Representative publication: Intrinsically disordered bacterial polar organizing protein Z, PopZ, interacts with protein binding partners through an N-terminal Molecular Recognition Feature. J Mol Bio (2020) 432: 6092-6107.
❸ Chiral quantum dots
Quantum dots (QDs) are nanometer size semiconductor crystals with excellent and tunable electronic and optical properties. Colloidal quantum dots consist of an inorganic semiconductor core (e.g., CdSe) and an organic capping ligand shell (e.g., cysteine). In collaboration with Dr. Milan Balaz (Yonsei University), we aim to determine how chiral organic ligands induce chiroptical activity in achiral semiconductor QDs and how QDs can be used to enhance the chiroptical signal of biomolecules. Chiral QDs are promising candidates for bioimaging, biosensing, environmental nanoassays, catalysis, and chiral memory.
- Representative publication: Threonine functionalized colloidal cadmium sulfide (CdS) quantum dots: The role of solvent and counterion in ligand induced chiroptical properties. J. Colloid Interface Sci (2023) 642: 771-778. https://doi.org/10.1016/j.jcis.2023.03.177
❹ Rates of protein evolution
In collaboration with Dr. David Alvarez-Ponze (University of Reno) and Dr. David Liberles (Temple University), we aim to identify the factors that have an important impact on the rates of protein evolution and elucidate the reasons why these factors affect rates of evolution. During evolution, different proteins accumulate amino acid changes at enormously different rates as a result of the different selective pressures to which they are subjected. We acknowledge support from NSF.