The internal organization of mycobacterial partition assembly: does the DNA wrap a protein core?
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 23285150.
- Also identified by DOI 10.1371/journal.pone.0052690 and PMC identifier PMC3481007.
- No licence information is recorded for this record.
- Because redistribution is not established, this page shows the abstract only. Follow the links below for the full text.
Abstract
Before cell division in many bacteria, the ParBs spread on a large segment of DNA encompassing the origin-proximal parS site(s) to form the partition assembly that participates in chromosome segregation. Little is known about the structural organization of chromosomal partition assembly. We report solution X-ray and neutron scattering data characterizing the size parameters and internal organization of a nucleoprotein assembly formed by the mycobacterial chromosomal ParB and a 120-meric DNA containing a parS-encompassing region from the mycobacterial genome. The cross-sectional radii of gyration and linear mass density describing the rod-like ParB-DNA assembly were determined from solution scattering. A "DNA outside, protein inside" mode of partition assembly organization consistent with the neutron scattering hydrogen/deuterium contrast variation data is discussed. In this organization, the high scattering DNA is positioned towards the outer region of the partition assembly. The new results presented here provide a basis for understanding how ParBs organize the parS-proximal chromosome, thus setting the stage for further interactions with the DNA condensins, the origin tethering factors and the ParA.