Professor Ioan Andricioaei
Department of Chemistry
University of Michigan
Ann Arbor, MI

Monday, April 12, 2004
3:00 pm (CT)
3269 Beckman Institute

Abstract

Molecular dynamics simulations are presented for a DNA polymerase I complex (consisting of the protein, the primer-template DNA strands, and the incoming nucleotide) subjected to external forces. The results obtained with force applied to the DNA template strand provide insights into the effect of the tension on the activity of the enzyme. At forces below 30 pN, a local model based on the parameters determined from the simulations, including the restricted motion of the DNA bases at the active site, yields a replication rate dependence on force in agreement with experiment. Simulations above 40 pN reveal large conformational changes in the enzyme-bound DNA that may have a role in the force- induced exonucleolysis observed experimentally.

Tea and coffee will be served in R3151 Beckman Institute at 2:15pm.