Year: 2025
Type: article
Abstract: Chromosomal sites in rod-like bacteria move sub-diffusely, driven by the out-of-equilibrium nature of the viscoelastic, crowded intracellular environment. Furthermore, it has been shown that there is a pronounced dynamical asymmetry between longitudinal (long-axis) and transverse (radial) motions, manifested in different exponents in the mean-square displacements $${MSD}\left(t\right) \sim {t}^{\alpha }$$, $${\alpha }_{{{\mathcal{l}}}}$$ and $${\alpha }_{{{r}}}$$ respectively. Here, using polymer simulations and experimental observations of a locus in Bacillus subtilis, we substantiate the notion that asymmetric dynamics are a result of the asymmetric structure of the bacterial chromosome modeled as a bottlebrush polymer in a poor solvent. Our simulations recapitulate the observed asymmetry as well as the range of the observed exponent values that are related to scaling models of polymer dynamics, lending support to the notion that asymmetric dynamics is a consequence of the bottlebrush structure of the bacterial chromosome. Anisotropic sub-diffusion of chromosomal loci in Bacillus subtilis arises from the bottlebrush chromosomal architecture, as shown by simulations and experiments, consistent with polymer scaling predictions in crowded, viscoelastic media.
Source: Communications Biology
Institutions: Northeastern University, Weizmann Institute of Science
Language: English
Subfield: Genetics
Domain: Life Sciences
Open Access status: gold
Estimated APC paid: $4,190
Awards: G3378106336, G579944473
OpenAlex ID: W4416553645