» Articles » PMID: 21903814

Chromosome Organization by a Nucleoid-associated Protein in Live Bacteria

Overview
Journal Science
Specialty Science
Date 2011 Sep 10
PMID 21903814
Citations 195
Authors
Affiliations
Soon will be listed here.
Abstract

Bacterial chromosomes are confined in submicrometer-sized nucleoids. Chromosome organization is facilitated by nucleoid-associated proteins (NAPs), but the mechanisms of action remain elusive. In this work, we used super-resolution fluorescence microscopy, in combination with a chromosome-conformation capture assay, to study the distributions of major NAPs in live Escherichia coli cells. Four NAPs--HU, Fis, IHF, and StpA--were largely scattered throughout the nucleoid. In contrast, H-NS, a global transcriptional silencer, formed two compact clusters per chromosome, driven by oligomerization of DNA-bound H-NS through interactions mediated by the amino-terminal domain of the protein. H-NS sequestered the regulated operons into these clusters and juxtaposed numerous DNA segments broadly distributed throughout the chromosome. Deleting H-NS led to substantial chromosome reorganization. These observations demonstrate that H-NS plays a key role in global chromosome organization in bacteria.

Citing Articles

Polyphosphate: The "Dark Matter" of Bacterial Chromatin Structure.

Racki L, Freddolino L Mol Microbiol. 2025; 123(3):279-293.

PMID: 39967274 PMC: 11894788. DOI: 10.1111/mmi.15350.


Macromolecular interactions and geometrical confinement determine the 3D diffusion of ribosome-sized particles in live cells.

Valverde-Mendez D, Sunol A, Bratton B, Delarue M, Hofmann J, Sheehan J Proc Natl Acad Sci U S A. 2025; 122(4):e2406340121.

PMID: 39854229 PMC: 11789073. DOI: 10.1073/pnas.2406340121.


Evolutionary and functional divergence of Sfx, a plasmid-encoded H-NS homolog, underlies the regulation of IncX plasmid conjugation.

Wang A, Cordova M, Navarre W mBio. 2024; 16(2):e0208924.

PMID: 39714162 PMC: 11796372. DOI: 10.1128/mbio.02089-24.


Hypothesis: bacteria live on the edge of phase transitions with a cell cycle regulated by a water-clock.

Norris V Theory Biosci. 2024; 143(4):253-277.

PMID: 39505803 DOI: 10.1007/s12064-024-00427-2.


Insight into Single-Molecule Imaging Techniques for the Study of Prokaryotic Genome Maintenance.

Sharma N, van Oijen A, Spenkelink L, Mueller S Chem Biomed Imaging. 2024; 2(9):595-614.

PMID: 39328428 PMC: 11423410. DOI: 10.1021/cbmi.4c00037.


References
1.
Grainger D, Hurd D, Goldberg M, Busby S . Association of nucleoid proteins with coding and non-coding segments of the Escherichia coli genome. Nucleic Acids Res. 2006; 34(16):4642-52. PMC: 1636352. DOI: 10.1093/nar/gkl542. View

2.
Reyes-Lamothe R, Wang X, Sherratt D . Escherichia coli and its chromosome. Trends Microbiol. 2008; 16(5):238-45. DOI: 10.1016/j.tim.2008.02.003. View

3.
Huang B, Babcock H, Zhuang X . Breaking the diffraction barrier: super-resolution imaging of cells. Cell. 2010; 143(7):1047-58. PMC: 3272504. DOI: 10.1016/j.cell.2010.12.002. View

4.
Smits W, Grossman A . The transcriptional regulator Rok binds A+T-rich DNA and is involved in repression of a mobile genetic element in Bacillus subtilis. PLoS Genet. 2010; 6(11):e1001207. PMC: 2978689. DOI: 10.1371/journal.pgen.1001207. View

5.
Eltsov M, Zuber B . Transmission electron microscopy of the bacterial nucleoid. J Struct Biol. 2006; 156(2):246-54. DOI: 10.1016/j.jsb.2006.07.007. View