National Biomedical Electron Paramagnetic Resonance Center

Education

I received my BS in Chemistry from the University of Madras (Madras, India) and my MS from the Indian Institute of Technology (Bombay, India). In 1978 I received my PhD in Chemistry from the University of Alabama (Tuscaloosa, AL) and trained as a postdoctoral fellow at the National Institute of Environmental Sciences (NIH). In 1981 I joined the Biophysics Section of the Department of Radiology at the Medical College of Wisconsin, and in 1984 I became an Assistant Professor in the Department of Radiology. Currently, I am Professor and Chairman of the Department of Biophysics. My research interests are centered on the application of EPR in free radical biology and understanding the role of free radicals in signal transduction and apoptosis. My specific research areas are outlined below. I have served as an Associate Editor for Free Radical Research and the Biochemical Journal, and currently serve as Associate Editor for Free Radicals in Biology and Medicine.

Research Team

• Gang Cheng, PhD (Postdoctoral Fellow)
• Brian Dranka, PhD (Postdoctoral Fellow)
• Alison Gifford (Research Technologist II)
• Steve Komas (Research Technologist I)
• Donna McAllister (Research Associate)
• Joy Joseph, PhD (Associate Professor)
• Gopit Shah, PhD (Postdoctoral Fellow)
• Jacek Zielonka, PhD (Research Scientist II, and Facility Manager, Free Radical Research Center)
• Monika Zielonka (Project Appointment)

Research Interests

Chemistry and Biophysics

• Detection of free radicals by EPR spin-trapping, fluorescence, optical stopped-flow, and HPLC techniques
• Syntheses of mitochondrially targeted spin traps, spin labels, and ROS-specific fluorescence probes
• EPR/ENDOR/NMR studies of active site geometry of redox-active enzymes (e.g., superoxide dismutase)
• Nitration of tyrosine- and tryptophan-containing peptides and protein (e.g., synucleins) in biological membranes

Mechanism of Signal Transduction/Cell Signaling

• Nitric oxide and cyclic nucleotide-dependent cell signaling and proteasomal activation
• Oxidant-induced iron signaling and apoptosis
• Redox proteomics
• Chemotherapeutic drug toxicity and prevention (e.g., doxorubicin); mechanism of apoptosis in tumor cells and normal cells

Mechanism of Disease

• Role of mitochondria-derived oxidants in chemically induced Parkinsonism (e.g., MPTP, rotenone) in cell culture and animal models; mechanism of protein aggregation, proteosomal dysfunction, and apoptotic neuronal cell death
• Oxidative stress and apoptosis induced by amyotrophic lateral sclerosis (Lou Gehrig's disease)/SOD1 mutants in cell culture and animal models; therapeutic intervention of disease progression in a G93A-transgenic animal model