Bacterial partition complexes segregate within the volume of the nucleoid

Nat Commun. 2016 Jul 5:7:12107. doi: 10.1038/ncomms12107.

Abstract

Precise and rapid DNA segregation is required for proper inheritance of genetic material. In most bacteria and archaea, this process is assured by a broadly conserved mitotic-like apparatus in which a NTPase (ParA) displaces the partition complex. Competing observations and models imply starkly different 3D localization patterns of the components of the partition machinery during segregation. Here we use super-resolution microscopies to localize in 3D each component of the segregation apparatus with respect to the bacterial chromosome. We show that Par proteins locate within the nucleoid volume and reveal that proper volumetric localization and segregation of partition complexes requires ATPase and DNA-binding activities of ParA. Finally, we find that the localization patterns of the different components of the partition system highly correlate with dense chromosomal regions. We propose a new mechanism in which the nucleoid provides a scaffold to guide the proper segregation of partition complexes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacillus subtilis / genetics*
  • Bacillus subtilis / metabolism
  • Bacillus subtilis / ultrastructure
  • Bacterial Proteins / genetics*
  • Bacterial Proteins / metabolism
  • Cell Compartmentation / genetics
  • Chromosome Segregation*
  • Chromosomes, Bacterial / chemistry
  • Chromosomes, Bacterial / metabolism
  • DNA Primase / genetics*
  • DNA Primase / metabolism
  • DNA, Bacterial / genetics*
  • DNA, Bacterial / metabolism
  • Escherichia coli / genetics*
  • Escherichia coli / metabolism
  • Escherichia coli / ultrastructure
  • Escherichia coli Proteins / genetics*
  • Escherichia coli Proteins / metabolism
  • Gene Expression
  • Protein Binding

Substances

  • Bacterial Proteins
  • DNA, Bacterial
  • Escherichia coli Proteins
  • chromosome partition proteins, bacterial
  • DNA Primase
  • dnaG protein, E coli