Jump to main content
Jump to site search

Issue 12, 2019
Previous Article Next Article

Confinement and crowding control the morphology and dynamics of a model bacterial chromosome

Author affiliations

Abstract

Motivated by recent experiments probing the shape, size and dynamics of bacterial chromosomes in growing cells, we consider a polymer model consisting of a circular backbone to which side-loops are attached, confined to a cylindrical cell. Such a model chromosome spontaneously adopts a helical shape, which is further compacted by molecular crowders to occupy a nucleoid-like sub-volume of the cell. With increasing cell length, the longitudinal size of the chromosome increases in a non-linear fashion until finally saturating, its morphology gradually opening up while displaying a changing number of helical turns. For shorter cells, the chromosome extension varies non-monotonically with cell size, which we show is associated with a radial to longitudinal spatial reordering of the crowders. Confinement and crowders constrain chain dynamics leading to anomalous diffusion. While the scaling exponent for the mean squared displacement of center of mass grows and saturates with cell length, that of individual loci displays a broad distribution with a sharp maximum.

Graphical abstract: Confinement and crowding control the morphology and dynamics of a model bacterial chromosome

Back to tab navigation

Publication details

The article was received on 13 Oct 2018, accepted on 13 Feb 2019 and first published on 18 Feb 2019


Article type: Paper
DOI: 10.1039/C8SM02092B
Citation: Soft Matter, 2019,15, 2677-2687

  •   Request permissions

    Confinement and crowding control the morphology and dynamics of a model bacterial chromosome

    P. Swain, B. M. Mulder and D. Chaudhuri, Soft Matter, 2019, 15, 2677
    DOI: 10.1039/C8SM02092B

Search articles by author

Spotlight

Advertisements