Book of Abstracts: Albany 2005
The Role of Nucleoid-associated Proteins in the Organization and Compaction of Bacterial Chromatin
Bacteria, like other organisms, are faced with the task of compacting their chromosomal DNA. In the case of E. coli, 4.6 Mb of DNA with a contour length of approximately 1.6 mm is fitted into a cell that is 2 µm long and has a diameter of about 1 µm. The combined action of several factors (DNA supercoiling, macromolecular crowding and nucleoid-associated proteins) results in a nucleoid that occupies only a small part of the intracellular volume.
A number of nucleoid-associated proteins (e.g. HU, H-NS, IHF, and Fis) is believed to be of essential importance for the dynamic organization and compaction of the bacterial chromatin. In addition, these proteins play specific roles in various cellular processes, among which transcription (1). Analysis of the interaction of H-NS (2) and HU (3, 4) with DNA using scanning force microscopy and ?single-molecule? stretching experiments has revealed how these proteins modulate DNA architecture. These experiments provide insight into the roles of these proteins as generic organizers of bacterial chromatin and as regulators of transcription.
References and Footnotes
Remus Th. Dame
Physics of Complex Systems