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| | ==E. coli Beta Sliding Clamp, 148-153 Ala Mutant== | | ==E. coli Beta Sliding Clamp, 148-153 Ala Mutant== |
| - | <StructureSection load='3f1v' size='340' side='right' caption='[[3f1v]], [[Resolution|resolution]] 1.77Å' scene=''> | + | <StructureSection load='3f1v' size='340' side='right'caption='[[3f1v]], [[Resolution|resolution]] 1.77Å' scene=''> |
| | == Structural highlights == | | == Structural highlights == |
| - | <table><tr><td colspan='2'>[[3f1v]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/"bacillus_coli"_migula_1895 "bacillus coli" migula 1895]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3F1V OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3F1V FirstGlance]. <br> | + | <table><tr><td colspan='2'>[[3f1v]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/"bacillus_coli"_migula_1895 "bacillus coli" migula 1895]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3F1V OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=3F1V FirstGlance]. <br> |
| - | </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=CA:CALCIUM+ION'>CA</scene>, <scene name='pdbligand=CL:CHLORIDE+ION'>CL</scene></td></tr> | + | </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=CA:CALCIUM+ION'>CA</scene>, <scene name='pdbligand=CL:CHLORIDE+ION'>CL</scene></td></tr> |
| - | <tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[1ok7|1ok7]]</td></tr> | + | <tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat"><div style='overflow: auto; max-height: 3em;'>[[1ok7|1ok7]]</div></td></tr> |
| - | <tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">dnaN, b3701, JW3678 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=562 "Bacillus coli" Migula 1895])</td></tr> | + | <tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">dnaN, b3701, JW3678 ([https://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=562 "Bacillus coli" Migula 1895])</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='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[https://en.wikipedia.org/wiki/DNA-directed_DNA_polymerase DNA-directed DNA polymerase], with EC number [https://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'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3f1v FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3f1v OCA], [http://pdbe.org/3f1v PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=3f1v RCSB], [http://www.ebi.ac.uk/pdbsum/3f1v PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=3f1v ProSAT]</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=3f1v FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3f1v OCA], [https://pdbe.org/3f1v PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=3f1v RCSB], [https://www.ebi.ac.uk/pdbsum/3f1v PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=3f1v ProSAT]</span></td></tr> |
| | </table> | | </table> |
| | == Function == | | == Function == |
| - | [[http://www.uniprot.org/uniprot/DPO3B_ECOLI DPO3B_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 beta chain is required for initiation of replication once it is clamped onto DNA, it slides freely (bidirectional and ATP-independent) along duplex DNA. | + | [[https://www.uniprot.org/uniprot/DPO3B_ECOLI DPO3B_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 beta chain is required for initiation of replication once it is clamped onto DNA, it slides freely (bidirectional and ATP-independent) along duplex DNA. |
| | == Evolutionary Conservation == | | == Evolutionary Conservation == |
| | [[Image:Consurf_key_small.gif|200px|right]] | | [[Image:Consurf_key_small.gif|200px|right]] |
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| | </div> | | </div> |
| | <div class="pdbe-citations 3f1v" style="background-color:#fffaf0;"></div> | | <div class="pdbe-citations 3f1v" style="background-color:#fffaf0;"></div> |
| - | | |
| - | ==See Also== | |
| - | *[[DNA polymerase|DNA polymerase]] | |
| | == References == | | == References == |
| | <references/> | | <references/> |
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| | [[Category: Bacillus coli migula 1895]] | | [[Category: Bacillus coli migula 1895]] |
| | [[Category: DNA-directed DNA polymerase]] | | [[Category: DNA-directed DNA polymerase]] |
| | + | [[Category: Large Structures]] |
| | [[Category: Cody, V]] | | [[Category: Cody, V]] |
| | [[Category: Dna replication]] | | [[Category: Dna replication]] |
| Structural highlights
Function
[DPO3B_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 beta chain is required for initiation of replication once it is clamped onto DNA, it slides freely (bidirectional and ATP-independent) along duplex DNA.
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
Sliding clamp proteins topologically encircle DNA and play vital roles in coordinating the actions of various DNA replication, repair, and damage tolerance proteins. At least three distinct surfaces of the Escherichia coli beta clamp interact physically with the DNA that it topologically encircles. We utilized mutant beta clamp proteins bearing G66E and G174A substitutions (beta159), affecting the single-stranded DNA-binding region, or poly-Ala substitutions in place of residues 148-HQDVR-152 (beta(148-152)), affecting the double-stranded DNA binding region, to determine the biological relevance of clamp-DNA interactions. As part of this work, we solved the X-ray crystal structure of beta(148-152), which verified that the poly-Ala substitutions failed to significantly alter the tertiary structure of the clamp. Based on functional assays, both beta159 and beta(148-152) were impaired for loading and retention on a linear primed DNA in vitro. In the case of beta(148-152), this defect was not due to altered interactions with the DnaX clamp loader, but rather was the result of impaired beta(148-152)-DNA interactions. Once loaded, beta(148-152) was proficient for DNA polymerase III (Pol III) replication in vitro. In contrast, beta(148-152) was severely impaired for Pol II and Pol IV replication and was similarly impaired for direct physical interactions with these Pols. Despite its ability to support Pol III replication in vitro, beta(148-152) was unable to support viability of E. coli. Nevertheless, physiological levels of beta(148-152) expressed from a plasmid efficiently complemented the temperature-sensitive growth phenotype of a strain expressing beta159 (dnaN159), provided that Pol II and Pol IV were inactivated. Although this strain was impaired for Pol V-dependent mutagenesis, inactivation of Pol II and Pol IV restored the Pol V mutator phenotype. Taken together, these results support a model in which a sophisticated combination of competitive clamp-DNA, clamp-partner, and partner-DNA interactions serve to manage the actions of the different E. coli Pols in vivo.
Sliding clamp-DNA interactions are required for viability and contribute to DNA polymerase management in Escherichia coli.,Heltzel JM, Scouten Ponticelli SK, Sanders LH, Duzen JM, Cody V, Pace J, Snell EH, Sutton MD J Mol Biol. 2009 Mar 20;387(1):74-91. Epub 2009 Jan 30. PMID:19361435[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Heltzel JM, Scouten Ponticelli SK, Sanders LH, Duzen JM, Cody V, Pace J, Snell EH, Sutton MD. Sliding clamp-DNA interactions are required for viability and contribute to DNA polymerase management in Escherichia coli. J Mol Biol. 2009 Mar 20;387(1):74-91. Epub 2009 Jan 30. PMID:19361435 doi:10.1016/j.jmb.2009.01.050
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