Physical modeling of active bacterial DNA segregation

Jean-Charles Walter (1)

1 L2C - Laboratoire Charles Coulomb

Efficient bacterial chromosome segregation typically requires the coordinated action of a three-component, fueled by adenosine triphosphate machinery called the partition complex. We present a phenomenological model accounting for the dynamic activity of this system that is also relevant for the physics of catalytic particles in active environments. The model is obtained by coupling simple linear reaction-diffusion equations with a proteophoresis, or “volumetric” chemophoresis, force field that arises from protein-protein interactions and provides a physically viable mechanism for complex translocation. This minimal description captures most known experimental observations: dynamic oscillations of complex components, complex separation and subsequent symmetrical positioning. The predictions of our model are in phenomenological agreement with and provide substantial insight into recent experiments. From a non-linear physics view point, this system explores the active separation of matter at micrometric scales with a dynamical instability between static positioning and travelling wave regimes triggered by the dynamical spontaneous breaking of rotational symmetry.

Domaines: Biophysique [physics.bio-ph]

Jean-Charles Walter. Physical modeling of active bacterial DNA segregation. Architecture et Dynamique Nucléaire (ADN), Mar 2017, Paris, France. ⟨hal-01931248⟩