Molecular basis for a protein-mediated DNA-bridging mechanism that functions in condensation of the E. coli chromosome.


Journal Article

The E. coli chromosome is condensed into insulated regions termed macrodomains (MDs), which are essential for genomic packaging. How chromosomal MDs are specifically organized and compacted is unknown. Here, we report studies revealing the molecular basis for Terminus-containing (Ter) chromosome condensation by the Ter-specific factor MatP. MatP contains a tripartite fold with a four-helix bundle DNA-binding motif, ribbon-helix-helix and C-terminal coiled-coil. Strikingly, MatP-matS structures show that the MatP coiled-coils form bridged tetramers that flexibly link distant matS sites. Atomic force microscopy and electron microscopy studies demonstrate that MatP alone loops DNA. Mutation of key coiled-coil residues destroys looping and causes a loss of Ter condensation in vivo. Thus, these data reveal the molecular basis for a protein-mediated DNA-bridging mechanism that mediates condensation of a large chromosomal domain in enterobacteria.

Full Text

Duke Authors

Cited Authors

  • Dupaigne, P; Tonthat, NK; Espéli, O; Whitfill, T; Boccard, F; Schumacher, MA

Published Date

  • November 30, 2012

Published In

Volume / Issue

  • 48 / 4

Start / End Page

  • 560 - 571

PubMed ID

  • 23084832

Pubmed Central ID

  • 23084832

Electronic International Standard Serial Number (EISSN)

  • 1097-4164

Digital Object Identifier (DOI)

  • 10.1016/j.molcel.2012.09.009


  • eng

Conference Location

  • United States