Physics Colloquium: Triggering DNA Condensation within the Bacterial Chromosome

Event Details

  • Speaker(s): Josh Milstein
  • Date:
  • Time: 4:00 PM
  • Location: MacN 101

Abstract

Bacterial DNA must be under varying levels of mechanical stress due to a high de-gree of crowding and repeated protein-DNA interactions experienced within the nucleoid. DNA tension is difficult to measure in cells and its currently not known if its effects have any functional significance; however, in vitro experiments have implicated a range of biomechanical phenomena. Using single-molecule tools, we discovered a novel protein-DNA interaction involving the nucleoid associated protein H-NS that responds to fluctuations in mechanical tension by irreversibly packaging DNA. Our results imply that bacteria may selectively condense DNA based upon the level of tension experienced along different regions of the chromosome.