My research focuses on the study of protein and nucleic acid structure with site-specificity utilizing a variety of spectroscopic methods including NMR and FTIR spectroscopy coupled with isotopic and/or chemical labels.
We use organic synthesis to build molecular knots and to make probes that are used to study nucleic acids. Our knot targets include the world's smallest knot, the first stable rotaxaknot, and the first small molecule figure eight knot. Our biochemical research involves using nitrile (R-CN) and azide (R-N3) vibrational probes to investigate the structure and dynamics of DNA and RNA. The probes give valuable information such as the electrostatic potential and the solvent dynamics in different microenvironments of the nucleic acid, i.e., major groove, minor groove, and sugar-backbone regions.
Elucidating the fundamental processes of glow discharge plasmas that lead to their analytical utility and expanding their applications in trace element analysis in diverse fields ranging from environmental monitoring to materials science.
Our research group has been investigating substituent effects on the [1,3] sigmatropic rearrangement of bicyclo[3.2.0]hept-2-ene. In collaboration with Dr. Richard Fluck in the Biology Department, we are also probing the function of cholinesterase in pea plants.
My research focuses on better understanding trace metal cycling in the marine environment. Since metals do not degrade, metal accumulation can be used to understand changes in the amount of metals being added to the marine environment and/or changes in conditions that affect metal accumulation over time. To improve our understanding of metal cycling, we study sediments obtained from marine waters. Because of the complexity of environmental samples, my research group also studies single mineral phases in conjunction with simple organic molecules in the laboratory to discern individual controls on metal adsorption that might be occurring in the environment. Both approaches provide us with information regarding metal sequestration in sediments under various conditions.
I am interested in the relationships between surface and solid-state properties of materials and their technologically important behavior. The size and composition of semiconductor particles affects how they absorb light and conduct electrical charge, and we use this to design particles effective in solar energy conversion devices. We also explore how the self-assembly of organic molecules into ordered monolayers at the liquid/solid interface influences solution and surface phenomena.
Solvent effects on solution photophysics.
Work in my lab will utilize a variety of biochemical techniques and will focus on understanding protein function through structure using X-ray crystallography. An overarching theme of the projects I am interested in is how cells sense and respond to their environment. One project uses in vitro techniques to study how the pathogenic bacteria Vibrio cholerae utilizes exogenous heme as an iron source for the cell while preventing the toxic side effects that heme could cause. Another project begins to investigate the protein interactions involved in a new nitric oxide (NO) signaling pathway in eukaryotes involving S-nitrosothiols. The third project aims to study the mechanism by which a bacterium involved in bioremediation of the environment, Dehalococcoides ethenogenes, senses and degrades the pollutant tetrachloroethene which is produced by dry cleaners and chemical industries.
Nucleophilic and electrophilic substitution reactions in ionic liquids. Photo-acid catalyzed organic reactions.
We are interested in the design, synthesis, and study of molecular devices that incorporate the elements of molecular recognition and host/guest chemistry. One category of such devices that we have focused on for the past few years is conformationally flexible host molecules that can be organized by an analyte to subsequently bind solvatochromic fluorescent indicators. This cooperative association can be used to signal the analyte binding event. Our novel design for fluorescent chemosensing may be applicable to the detection of low concentrations of so-called quenching heavy metal or transition metal ions in aqueous solution.
The structure and bonding in Group 14 nitrogen compounds
Hypercoordination in Group 14 compounds
The synthesis and characterization of mineralogically significant compounds
The synthesis and characterization of apatites and their carbonated analogs