1qhl
From Proteopedia
(New page: 200px<br /><applet load="1qhl" size="450" color="white" frame="true" align="right" spinBox="true" caption="1qhl, resolution 2.2Å" /> '''CRYSTAL STRUCTURE OF ...) |
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| - | [[Image:1qhl.jpg|left|200px]]<br /><applet load="1qhl" size=" | + | [[Image:1qhl.jpg|left|200px]]<br /><applet load="1qhl" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1qhl, resolution 2.2Å" /> | caption="1qhl, resolution 2.2Å" /> | ||
'''CRYSTAL STRUCTURE OF THE N-TERMINAL DOMAIN OF MUKB AT 2.2A RESOLUTION'''<br /> | '''CRYSTAL STRUCTURE OF THE N-TERMINAL DOMAIN OF MUKB AT 2.2A RESOLUTION'''<br /> | ||
==Overview== | ==Overview== | ||
| - | BACKGROUND: The 170 kDa protein MukB has been implicated in ATP-dependent | + | BACKGROUND: The 170 kDa protein MukB has been implicated in ATP-dependent chromosome partitioning during cell division in Escherichia coli. MukB shares its dimeric structure and domain architecture with the ubiquitous family of SMC (structural maintenance of chromosomes) proteins that facilitate similar functions. The N-terminal domain of MukB carries a putative Walker A nucleotide-binding region and the C-terminal domain has been shown to bind to DNA. Mutant phenotypes and a domain arrangement similar to motor proteins that move on microtubules led to the suggestion that MukB might be a motor protein acting on DNA. RESULTS: We have cloned, overexpressed and crystallized a 26 kDa protein consisting of 227 N-terminal residues of MukB from E. coli. The structure has been solved using multiple anomalous dispersion and has been refined to 2.2 A resolution. The N-terminal domain of MukB has a mixed alpha/beta fold with a central six-stranded antiparallel beta sheet. The putative nucleotide-binding loop, which is part of an unexpected helix-loop-helix motif, is exposed on the surface and no nucleotide-binding pocket could be detected. CONCLUSIONS: The N-terminal domain of MukB has no similarity to the kinesin family of motor proteins or to any other nucleotide-binding protein. Together with the finding of the exposed Walker A motif this observation supports a model in which the N- and C-terminal domains come together in the dimer of MukB to form the active site. Conserved residues on one side of the molecule delineate a region of the N-terminal domain that is likely to interact with the C-terminal domain. |
==About this Structure== | ==About this Structure== | ||
| - | 1QHL is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full crystallographic information is available from [http:// | + | 1QHL is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1QHL OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Escherichia coli]] | [[Category: Escherichia coli]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Ent, F | + | [[Category: Ent, F van den.]] |
[[Category: Lowe, J.]] | [[Category: Lowe, J.]] | ||
[[Category: chromosome partitioning]] | [[Category: chromosome partitioning]] | ||
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[[Category: smc]] | [[Category: smc]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 14:39:42 2008'' |
Revision as of 12:39, 21 February 2008
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CRYSTAL STRUCTURE OF THE N-TERMINAL DOMAIN OF MUKB AT 2.2A RESOLUTION
Overview
BACKGROUND: The 170 kDa protein MukB has been implicated in ATP-dependent chromosome partitioning during cell division in Escherichia coli. MukB shares its dimeric structure and domain architecture with the ubiquitous family of SMC (structural maintenance of chromosomes) proteins that facilitate similar functions. The N-terminal domain of MukB carries a putative Walker A nucleotide-binding region and the C-terminal domain has been shown to bind to DNA. Mutant phenotypes and a domain arrangement similar to motor proteins that move on microtubules led to the suggestion that MukB might be a motor protein acting on DNA. RESULTS: We have cloned, overexpressed and crystallized a 26 kDa protein consisting of 227 N-terminal residues of MukB from E. coli. The structure has been solved using multiple anomalous dispersion and has been refined to 2.2 A resolution. The N-terminal domain of MukB has a mixed alpha/beta fold with a central six-stranded antiparallel beta sheet. The putative nucleotide-binding loop, which is part of an unexpected helix-loop-helix motif, is exposed on the surface and no nucleotide-binding pocket could be detected. CONCLUSIONS: The N-terminal domain of MukB has no similarity to the kinesin family of motor proteins or to any other nucleotide-binding protein. Together with the finding of the exposed Walker A motif this observation supports a model in which the N- and C-terminal domains come together in the dimer of MukB to form the active site. Conserved residues on one side of the molecule delineate a region of the N-terminal domain that is likely to interact with the C-terminal domain.
About this Structure
1QHL is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.
Reference
Crystal structure of the N-terminal domain of MukB: a protein involved in chromosome partitioning., van den Ent F, Lockhart A, Kendrick-Jones J, Lowe J, Structure. 1999 Oct 15;7(10):1181-7. PMID:10545328
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