3uiq

<StructureSection load='3uiq' size='340' side='right' caption='[[3uiq]], [[Resolution|resolution]] 1.88&Aring;' scene=''>

<table><tr><td colspan='2'>[[3uiq]] is a 3 chain structure with sequence from [http://en.wikipedia.org/wiki/Enterobacteria_phage_rb69 Enterobacteria phage rb69]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3UIQ OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3UIQ FirstGlance]. <br>

</td></tr><tr><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=CA:CALCIUM+ION'>CA</scene>, <scene name='pdbligand=DUP:2-DEOXYURIDINE+5-ALPHA,BETA-IMIDO-TRIPHOSPHATE'>DUP</scene><br>

<tr><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">43 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=12353 Enterobacteria phage RB69])</td></tr>

<tr><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><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3uiq FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3uiq OCA], [http://www.rcsb.org/pdb/explore.do?structureId=3uiq RCSB], [http://www.ebi.ac.uk/pdbsum/3uiq PDBsum]</span></td></tr>

<table>

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== Publication Abstract from PubMed ==

Two divalent metal ions are required for primer-extension catalyzed by DNA polymerases. One metal ion brings the 3'-hydroxyl of the primer terminus and the alpha-phosphorus atom of incoming dNTP together for bond formation so that the catalytically relevant conformation of the triphosphate tail of the dNTP is in an alpha,beta,gamma-tridentate coordination complex with the second metal ion required for proper substrate alignment. A probable base selectivity mechanism derived from structural studies on Dpo4 suggests that the inability of mispaired dNTPs to form a substrate-aligned, tridentate coordination complex could effectively cause the mispaired dNTPs to be rejected before catalysis. Nevertheless, we found that mispaired dNTPs can actually form a properly aligned tridentate coordination complex. However, complementary dNTPs occasionally form misaligned complexes with mutant RB69 DNA polymerases (RB69pols) that are not in a tridentate coordination state. Here, we report finding a beta,gamma-bidentate coordination complex that contained the complementary dUpNpp opposite dA in the structure of a ternary complex formed by the wild type RB69pol at 1.88 A resolution. Our observations suggest that several distinct metal-ion coordination states can exist at the ground state in the polymerase active site and that base selectivity is unlikely to be based on metal-ion coordination alone.

 

 

*[[DNA polymerase|DNA polymerase]]

[[Category: DNA-directed DNA polymerase]]

[[Category: Enterobacteria phage rb69]]

[[Category: Konigsberg, W H.]]

[[Category: Wang, J.]]

[[Category: Xia, S.]]

[[Category: Wt]]