CURRENT RESEARCH PROJECTS

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 John Tsavalas (University of New Hamsphire), Paul Baures (Keene State College), and Emily Asenath-Smith (Cold Regions Research and Engineering Laboratory). This project is supported by NASA-EPSCoR and NIH.

Chiral nanoparticles
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 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.

Regulators of G-protein signaling proteins
The discoveries of a class of intracellular regulatory proteins known as regulators of G-protein signaling (RGS) proteins that mediate GPCR signaling via  protein-protein interactions between the RGS domains and the gamma-subunit of G-proteins and their covalent inhibitors have opened a new venue for allosteric targeting in GPCRs. In collaboration with Rick Neubig (Michigan State University) and Harish Vashisth (University of New Hampshire), we are studying inhibitor-induced structural perturbations using NMR and MD analyses of the RGS8 protein and its mutant forms to understand the role of cysteine residues in affecting potency and specificity of inhibitors. This project is supported by NIH.

Rates of protein evolution
In collaboration with David Alvarez-Ponze (University of Reno) and 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. This project is supported by NSF.

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 Grant Bowman at the University of Wyoming. This project is supported by NIH.