COLLOQUIUM 2025

Abstract

The millimeter- to meter-long DNA molecules – millions to billions of base-pairs in length – that carry genetic information in cells, are precisely read, replicated and repaired so that living things can grow and reproduce. This is done by an array of enzyme complexes that organize DNA structure, geometry and topology at nanometer scales using forces in the piconewton range. I will review some of the features of cellular DNA-processing machinery, and describe single-DNA-based “single-molecule” methods that allow us to observe the dynamics of interactions between small numbers or even individual biomolecules. Such studies of individual “molecular machines” can be well-described using equilibrium and nonequilibrium statistical physics. I will also discuss experiments applying micromechanical approaches to studies of large-scale chromosome organization.