DPG Phi
Verhandlungen
Verhandlungen
DPG

Berlin 2012 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

BP: Fachverband Biologische Physik

BP 13: DNA/RNA and Related Enzymes

BP 13.1: Topical Talk

Wednesday, March 28, 2012, 09:30–10:00, H 1058

Chemo-mechanics of a ring-shaped helicase during unwinding — •Michael Schlierf1,2, Ganggang Wang3, Xiaojiang Chen3, and Taekjip Ha1,41University of Illinois at Urbana-Champaign, Physics Department and Center for Physics of Living Cells, Urbana, Illinois — 2B CUBE - Center for Molecular Bioengineering, TU Dresden — 3University of Southern California, Department of Biological Sciences — 4Howard Hughes Medical Institute, Urbana, Illinois

Most replicative helicases are hexameric ring-shaped enzymes and are essential for cell survival. Despite extensive biochemical, structural and single-molecule investigations, how the translocation activities are utilized in the mechanical process of dsDNA unwinding are poorly understood. We investigated DnaB-family helicase G40P using a single molecule fluorescence-based unwinding assay with a single base pair resolution. The high-resolution assay revealed that G40P is an ultra-weak helicase that stalls at barriers as small as a single GC base pair and is a motor that moves with the step size of a single base pair. We directly observed the long-postulated activity of helicase slippage that is markedly enhanced under conditions that slow forward progression, but is fully suppressed by the primase DnaG.

100% | Mobile Layout | Deutsche Version | Contact/Imprint/Privacy
DPG-Physik > DPG-Verhandlungen > 2012 > Berlin