The emphasis in the Molecular Biophysics Program is on free radicals and paramagnetic metal ions in biological systems.
Free Radicals Free radicals generally have a bad press as their production is associated with many diseases, such as atherosclerosis and Lou Gehrig's disease, and are also largely responsible for the unhealthy effects of air pollution. Most people are surprised to learn that many free radicals are stable molecules and that biological systems purposely make free radicals as paracrine hormones. The free radical nitric oxide (NO) is involved in the control of blood pressure, memory and inflammation, and is a major focus of research at the Department of Biophysics. Free radicals have been used for many years to probe metal ion-containing sites of proteins, such as hemoglobin.
Spin Labels Advances in genetic engineering now make it possible to introduce free radicals at any site in a protein by a technique known as site-directed spin labeling. Free radicals are excellent reporters of their environment and therefore can be used to investigate protein structure and dynamics. Site-directed spin labeling studies of bacterial pores (used to control the flow of chemical into and out of cells), as well as other proteins, are being conducted in our department.
Metal Ions Paramagnetic metals are involved in all aspects of biology. The enzyme ribonucleotide reductase, for example, contains both a tyrosyl free radical and a mu-oxo dinuclear iron center. The anti-tumor agent iron bleomycin damages DNA by free radical chemistry. The free radical scavenging enzyme, superoxide dismutase, contains an active site copper that may be important in Lou Gehrig's disease.