Chromosome organization by a conserved condensin-ParB system in the actinobacterium Corynebacterium glutamicum

Nat Commun. 2020 Mar 20;11(1):1485. doi: 10.1038/s41467-020-15238-4.


Higher-order chromosome folding and segregation are tightly regulated in all domains of life. In bacteria, details on nucleoid organization regulatory mechanisms and function remain poorly characterized, especially in non-model species. Here, we investigate the role of DNA-partitioning protein ParB and SMC condensin complexes in the actinobacterium Corynebacterium glutamicum. Chromosome conformation capture reveals SMC-mediated long-range interactions around ten centromere-like parS sites clustered at the replication origin (oriC). At least one oriC-proximal parS site is necessary for reliable chromosome segregation. We use chromatin immunoprecipitation and photoactivated single-molecule localization microscopy to show the formation of distinct, parS-dependent ParB-nucleoprotein subclusters. We further show that SMC/ScpAB complexes, loaded via ParB at parS sites, mediate chromosomal inter-arm contacts (as previously shown in Bacillus subtilis). However, the MukBEF-like SMC complex MksBEFG does not contribute to chromosomal DNA-folding; instead, this complex is involved in plasmid maintenance and interacts with the polar oriC-tethering factor DivIVA. Our results complement current models of ParB-SMC/ScpAB crosstalk and show that some condensin complexes evolved functions that are apparently uncoupled from chromosome folding.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenosine Triphosphatases / metabolism*
  • Bacillus subtilis
  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism
  • Centromere / metabolism
  • Chromosome Segregation
  • Chromosome Structures / chemistry*
  • Chromosome Structures / metabolism*
  • Chromosomes, Bacterial / chemistry*
  • Chromosomes, Bacterial / genetics
  • Chromosomes, Bacterial / metabolism*
  • Corynebacterium glutamicum / metabolism*
  • DNA Primase / genetics
  • DNA Primase / metabolism
  • DNA, Bacterial
  • DNA-Binding Proteins / metabolism*
  • Multiprotein Complexes / metabolism*
  • Nucleoproteins / metabolism
  • Replication Origin


  • Bacterial Proteins
  • DNA, Bacterial
  • DNA-Binding Proteins
  • Multiprotein Complexes
  • Nucleoproteins
  • chromosome partition proteins, bacterial
  • condensin complexes
  • DNA Primase
  • Adenosine Triphosphatases