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| | ==Structure of the E. coli SSB-DNA polymerase III interface== | | ==Structure of the E. coli SSB-DNA polymerase III interface== |
| - | <StructureSection load='3sxu' size='340' side='right' caption='[[3sxu]], [[Resolution|resolution]] 1.85Å' scene=''> | + | <StructureSection load='3sxu' size='340' side='right'caption='[[3sxu]], [[Resolution|resolution]] 1.85Å' scene=''> |
| | == Structural highlights == | | == Structural highlights == |
| - | <table><tr><td colspan='2'>[[3sxu]] is a 3 chain structure with sequence from [http://en.wikipedia.org/wiki/Ecoli Ecoli]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3SXU OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3SXU FirstGlance]. <br> | + | <table><tr><td colspan='2'>[[3sxu]] is a 3 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_coli_K-12 Escherichia coli K-12]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3SXU OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=3SXU FirstGlance]. <br> |
| - | </td></tr><tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">b4259, holC, JW4216 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=83333 ECOLI]), b4372, holD, JW4334 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=83333 ECOLI])</td></tr> | + | </td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 1.85Å</td></tr> |
| - | <tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/DNA-directed_DNA_polymerase DNA-directed DNA polymerase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.7.7.7 2.7.7.7] </span></td></tr>
| + | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=3sxu FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3sxu OCA], [https://pdbe.org/3sxu PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=3sxu RCSB], [https://www.ebi.ac.uk/pdbsum/3sxu PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=3sxu ProSAT]</span></td></tr> |
| - | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3sxu FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3sxu OCA], [http://pdbe.org/3sxu PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=3sxu RCSB], [http://www.ebi.ac.uk/pdbsum/3sxu PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=3sxu ProSAT]</span></td></tr> | + | |
| | </table> | | </table> |
| | == Function == | | == Function == |
| - | [[http://www.uniprot.org/uniprot/HOLC_ECOLI HOLC_ECOLI]] DNA polymerase III is a complex, multichain enzyme responsible for most of the replicative synthesis in bacteria. This DNA polymerase also exhibits 3' to 5' exonuclease activity. [[http://www.uniprot.org/uniprot/HOLD_ECOLI HOLD_ECOLI]] DNA polymerase III is a complex, multichain enzyme responsible for most of the replicative synthesis in bacteria. This DNA polymerase also exhibits 3' to 5' exonuclease activity. The exact function of the psi subunit is unknown. | + | [https://www.uniprot.org/uniprot/HOLC_ECOLI HOLC_ECOLI] DNA polymerase III is a complex, multichain enzyme responsible for most of the replicative synthesis in bacteria. This DNA polymerase also exhibits 3' to 5' exonuclease activity. |
| - | <div style="background-color:#fffaf0;">
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| - | == Publication Abstract from PubMed ==
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| - | Interactions between single-stranded DNA-binding proteins (SSBs) and the DNA replication machinery are found in all organisms, but the roles of these contacts remain poorly defined. In Escherichia coli, SSB's association with the chi subunit of the DNA polymerase III holoenzyme has been proposed to confer stability to the replisome and to aid delivery of primers to the lagging-strand DNA polymerase. Here, the SSB-binding site on chi is identified crystallographically and biochemical and cellular studies delineate the consequences of destabilizing the chi/SSB interface. An essential role for the chi/SSB interaction in lagging-strand primer utilization is not supported. However, sequence changes in chi that block complex formation with SSB lead to salt-dependent uncoupling of leading- and lagging-strand DNA synthesis and to a surprising obstruction of the leading-strand DNA polymerase in vitro, pointing to roles for the chi/SSB complex in replisome establishment and maintenance. Destabilization of the chi/SSB complex in vivo produces cells with temperature-dependent cell cycle defects that appear to arise from replisome instability.
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| - | Structure of the SSB-DNA polymerase III interface and its role in DNA replication.,Marceau AH, Bahng S, Massoni SC, George NP, Sandler SJ, Marians KJ, Keck JL EMBO J. 2011 Aug 19. doi: 10.1038/emboj.2011.305. PMID:21857649<ref>PMID:21857649</ref>
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| - | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br>
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| - | </div>
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| - | <div class="pdbe-citations 3sxu" style="background-color:#fffaf0;"></div>
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| | ==See Also== | | ==See Also== |
| - | *[[DNA polymerase|DNA polymerase]] | + | *[[DNA polymerase 3D structures|DNA polymerase 3D structures]] |
| - | == References ==
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| - | <references/>
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| | __TOC__ | | __TOC__ |
| | </StructureSection> | | </StructureSection> |
| - | [[Category: DNA-directed DNA polymerase]] | + | [[Category: Escherichia coli K-12]] |
| - | [[Category: Ecoli]] | + | [[Category: Large Structures]] |
| - | [[Category: Keck, J L]] | + | [[Category: Keck JL]] |
| - | [[Category: Marceau, A H]] | + | [[Category: Marceau AH]] |
| - | [[Category: Chi binds to ssb and psi]]
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| - | [[Category: Dna replication]]
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| - | [[Category: Transferase]]
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