Structural highlights
Function
[MUKB_ECOLI] Plays a central role in chromosome condensation, segregation and cell cycle progression. Functions as a homodimer, which is essential for chromosome partition. Involved in negative DNA supercoiling in vivo, and by this means organizes and compacts chromosomes. May achieve or facilitate chromosome segregation by condensation of DNA from both sides of a centrally located replisome during cell division. Stimulates both DNA relaxation and to a lesser extent decatenation activity of topoisomerase IV.[1] [2]
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
MukB, a divergent structural maintenance of chromosomes (SMC) protein, is important for chromosomal segregation and condensation in gamma-proteobacteria. MukB and canonical SMC proteins share a characteristic five-domain structure. Globular N- and C-terminal domains interact to form an ATP-binding cassette-like ATPase or "head" domain, which is connected to a smaller dimerization or "hinge" domain by a long, antiparallel coiled coil. In addition to mediating dimerization, this hinge region has been implicated in both conformational flexibility and dynamic protein-DNA interactions. We report here the first crystallographic model of the MukB hinge domain. This model also contains approximately 20% of the coiled-coil domain, including an unusual coiled-coil deviation. These results will facilitate studies to clarify the roles of both the hinge and the coiled-coil domains in MukB function.
The crystal structure of the hinge domain of the Escherichia coli structural maintenance of chromosomes protein MukB.,Li Y, Schoeffler AJ, Berger JM, Oakley MG J Mol Biol. 2010 Jan 8;395(1):11-9. Epub 2009 Oct 22. PMID:19853611[3]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Li Y, Stewart NK, Berger AJ, Vos S, Schoeffler AJ, Berger JM, Chait BT, Oakley MG. Escherichia coli condensin MukB stimulates topoisomerase IV activity by a direct physical interaction. Proc Natl Acad Sci U S A. 2010 Nov 2;107(44):18832-7. doi:, 10.1073/pnas.1008678107. Epub 2010 Oct 4. PMID:20921377 doi:http://dx.doi.org/10.1073/pnas.1008678107
- ↑ Sawitzke JA, Austin S. Suppression of chromosome segregation defects of Escherichia coli muk mutants by mutations in topoisomerase I. Proc Natl Acad Sci U S A. 2000 Feb 15;97(4):1671-6. PMID:10660686 doi:http://dx.doi.org/10.1073/pnas.030528397
- ↑ Li Y, Schoeffler AJ, Berger JM, Oakley MG. The crystal structure of the hinge domain of the Escherichia coli structural maintenance of chromosomes protein MukB. J Mol Biol. 2010 Jan 8;395(1):11-9. Epub 2009 Oct 22. PMID:19853611 doi:S0022-2836(09)01280-7
