“Form and Function: Molecular Machines at the Nanoscale”
2011 Symposium Keynote Speakers
Michael F. Summers
Summers is professor of chemistry and biochemistry at the University of Maryland, Baltimore County, adjunct professor of biological chemistry at the University of Maryland School of Medicine in Baltimore, and HHMI investigator.
Summers is unraveling the internal architecture of HIV. A mentor with UMBC’s Meyerhoff Program, Summers and his students aim to design new therapeutic treatments for diseases caused by retroviruses.
In recent years, Summers has uncovered a molecular switching mechanism that plays an important role in HIV infection. When the switch is “on,” the Gag protein complex binds tightly to the membrane of an infected cell so that the virus can assemble. After the virus forms and buds off, the switch turns “off.” Only then is Gag cleaved into its component parts, a process that transforms newly formed but immature HIV into a mature virus that is capable of infecting other cells. Summers has also identified a new class of compounds that inhibit a key protein involved in the transformation of HIV into its mature form.
Summers’ mentoring has earned him as much praise in some circles as his achievements in the laboratory. More than 120 undergraduates have trained in his lab, about half of them African Americans, and most go on to highly regarded Ph.D. or M.D.-Ph.D. programs.
“While I am very proud of our research, I think it is the work I’ve done with the students that brings me the greatest personal satisfaction and may, in the end, be of greatest importance,” he says.
Professor of Physics, Chemistry, and Molecular and Cell Biology Carlos Bustamante investigates the machine-like behavior of molecular motors at the University of California at Berkeley.
Bustamante uses novel methods of single-molecule visualization, such as scanning force microscopy, to study the structure and function of nucleoprotein assemblies. His laboratory is developing methods of single-molecule manipulation, such as optical and magnetic tweezers, to characterize the elasticity of DNA, to induce the mechanical unfolding of individual protein and RNA molecules, and to investigate the machine-like behavior of molecular motors.
Living cells maintain a constant buzz of molecular activity. Molecular motors power the shuttling of proteins to their specific destinations, the curling and twisting of enzymes as they burrow into their substrates, and the unwinding and copying of DNA. Using magnetic beads, an atomic force microscope, and laser tweezers, Bustamante has developed innovative ways to investigate the physical forces that drive the movement of individual molecules within cells. His discoveries are revealing a deeper understanding of the inner workings of the cell.