Bacterial chromatin as a phase-separating nematic elastomer

Upon stress, bacteria compact their chromosomes into condensates to protect their genome from damage. These condensates are organized by proteins (Dps) that cooperatively bind with the DNA. The resulting DNA-Dps structure is a polymer network characterized by local nematic order and viscoelastic properties. Towards understanding the rheology and phase separation dynamics, we examine a minimal continuum model that couples Cahn-Hilliard phase separation with the Landau-de Gennes theory of liquid crystals and an elastic strain model. While the ground state of the material is ordered, the strain of the polymer network that emerges during the dynamics of phase separation can create long-lasting disorder in the material that impacts its mechanical properties.