2iso: Difference between revisions
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==Ternary complex of DNA Polymerase beta with a dideoxy terminated primer and 2'-deoxyguanosine 5'-beta, gamma-difluoromethylene triphosphate== | ==Ternary complex of DNA Polymerase beta with a dideoxy terminated primer and 2'-deoxyguanosine 5'-beta, gamma-difluoromethylene triphosphate== | ||
<StructureSection load='2iso' size='340' side='right' caption='[[2iso]], [[Resolution|resolution]] 2.10Å' scene=''> | <StructureSection load='2iso' size='340' side='right'caption='[[2iso]], [[Resolution|resolution]] 2.10Å' scene=''> | ||
== Structural highlights == | == Structural highlights == | ||
<table><tr><td colspan='2'>[[2iso]] is a 4 chain structure with sequence from [ | <table><tr><td colspan='2'>[[2iso]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Human Human]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2ISO OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2ISO FirstGlance]. <br> | ||
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=CL:CHLORIDE+ION'>CL</scene>, <scene name='pdbligand=GFF:2-DEOXY-5-O-[({[DIFLUORO(PHOSPHONO)METHYL](HYDROXY)PHOSPHORYL}OXY)(HYDROXY)PHOSPHORYL]GUANOSINE'>GFF</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=NA:SODIUM+ION'>NA</scene></td></tr> | </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=CL:CHLORIDE+ION'>CL</scene>, <scene name='pdbligand=GFF:2-DEOXY-5-O-[({[DIFLUORO(PHOSPHONO)METHYL](HYDROXY)PHOSPHORYL}OXY)(HYDROXY)PHOSPHORYL]GUANOSINE'>GFF</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=NA:SODIUM+ION'>NA</scene></td></tr> | ||
<tr id='NonStdRes'><td class="sblockLbl"><b>[[Non-Standard_Residue|NonStd Res:]]</b></td><td class="sblockDat"><scene name='pdbligand=DOC:2,3-DIDEOXYCYTIDINE-5-MONOPHOSPHATE'>DOC</scene></td></tr> | <tr id='NonStdRes'><td class="sblockLbl"><b>[[Non-Standard_Residue|NonStd Res:]]</b></td><td class="sblockDat"><scene name='pdbligand=DOC:2,3-DIDEOXYCYTIDINE-5-MONOPHOSPHATE'>DOC</scene></td></tr> | ||
<tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[2isp|2isp]]</td></tr> | <tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat"><div style='overflow: auto; max-height: 3em;'>[[2isp|2isp]]</div></td></tr> | ||
<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">POLB ([ | <tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">POLB ([https://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=9606 HUMAN])</td></tr> | ||
<tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[ | <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'>[ | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=2iso FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2iso OCA], [https://pdbe.org/2iso PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2iso RCSB], [https://www.ebi.ac.uk/pdbsum/2iso PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2iso ProSAT]</span></td></tr> | ||
</table> | </table> | ||
== Function == | == Function == | ||
[[ | [[https://www.uniprot.org/uniprot/DPOLB_HUMAN DPOLB_HUMAN]] Repair polymerase that plays a key role in base-excision repair. Has 5'-deoxyribose-5-phosphate lyase (dRP lyase) activity that removes the 5' sugar phosphate and also acts as a DNA polymerase that adds one nucleotide to the 3' end of the arising single-nucleotide gap. Conducts 'gap-filling' DNA synthesis in a stepwise distributive fashion rather than in a processive fashion as for other DNA polymerases.<ref>PMID:9207062</ref> <ref>PMID:9572863</ref> <ref>PMID:11805079</ref> <ref>PMID:21362556</ref> | ||
== 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 2iso" style="background-color:#fffaf0;"></div> | <div class="pdbe-citations 2iso" style="background-color:#fffaf0;"></div> | ||
== References == | == References == | ||
<references/> | <references/> | ||
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[[Category: DNA-directed DNA polymerase]] | [[Category: DNA-directed DNA polymerase]] | ||
[[Category: Human]] | [[Category: Human]] | ||
[[Category: Large Structures]] | |||
[[Category: Beard, W A]] | [[Category: Beard, W A]] | ||
[[Category: Kashemirov, B A]] | [[Category: Kashemirov, B A]] | ||
Revision as of 14:21, 31 March 2021
Ternary complex of DNA Polymerase beta with a dideoxy terminated primer and 2'-deoxyguanosine 5'-beta, gamma-difluoromethylene triphosphateTernary complex of DNA Polymerase beta with a dideoxy terminated primer and 2'-deoxyguanosine 5'-beta, gamma-difluoromethylene triphosphate
Structural highlights
Function[DPOLB_HUMAN] Repair polymerase that plays a key role in base-excision repair. Has 5'-deoxyribose-5-phosphate lyase (dRP lyase) activity that removes the 5' sugar phosphate and also acts as a DNA polymerase that adds one nucleotide to the 3' end of the arising single-nucleotide gap. Conducts 'gap-filling' DNA synthesis in a stepwise distributive fashion rather than in a processive fashion as for other DNA polymerases.[1] [2] [3] [4] 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 PubMedDNA polymerase catalysis and fidelity studies typically compare incorporation of "right" versus "wrong" nucleotide bases where the leaving group is pyrophosphate. Here we use dGTP analogues replacing the beta,gamma-bridging O with CH2, CHF, CF2, or CCl2 to explore leaving-group effects on the nucleotidyl transfer mechanism and fidelity of DNA polymerase (pol) beta. T.G mismatches occur with fidelities similar to dGTP with the exception of the CH2 analogue, which is incorporated with 5-fold higher fidelity. All analogues are observed to bind opposite template C with Kds between 1 and 4 microM, and structural evidence suggests that the analogues bind in essentially the native conformation, making them suitable substrates for probing linear free energy relationships (LFERs) in transient-kinetics experiments. Importantly, Brnsted correlations of log(kpol) versus leaving-group pKa for both right and wrong base incorporation reveal similar sensitivities (betalg approximately -0.8) followed by departures from linearity, suggesting that a chemical step rather than enzyme conformational change is rate-limiting for either process. The location of the breaks relative to pKas of CF2, O, and the sterically bulky CCl2-bridging compounds suggests a modification-induced change in the mechanism by stabilization of leaving-group elimination. The results are addressed theoretically in terms of the energetics of successive primer 3'-O addition (bond forming) and pyrophosphate analogue elimination (bond breaking) reaction energy barriers. Modifying the beta,gamma leaving-group bridging oxygen alters nucleotide incorporation efficiency, fidelity, and the catalytic mechanism of DNA polymerase beta.,Sucato CA, Upton TG, Kashemirov BA, Batra VK, Martinek V, Xiang Y, Beard WA, Pedersen LC, Wilson SH, McKenna CE, Florian J, Warshel A, Goodman MF Biochemistry. 2007 Jan 16;46(2):461-71. PMID:17209556[5] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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