View source for 3aqn


==Complex structure of bacterial protein (apo form II)==
<StructureSection load='3aqn' size='340' side='right'caption='[[3aqn]], [[Resolution|resolution]] 3.30&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[3aqn]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_coli_DH1 Escherichia coli DH1]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3AQN OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=3AQN FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 3.3&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=ATP:ADENOSINE-5-TRIPHOSPHATE'>ATP</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene></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=3aqn FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3aqn OCA], [https://pdbe.org/3aqn PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=3aqn RCSB], [https://www.ebi.ac.uk/pdbsum/3aqn PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=3aqn ProSAT]</span></td></tr>
</table>
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
PolyA polymerase (PAP) adds a polyA tail onto the 3'-end of RNAs without a nucleic acid template, using adenosine-5'-triphosphate (ATP) as a substrate. The mechanism for the substrate selection by eubacterial PAP remains obscure. Structural and biochemical studies of Escherichia coli PAP (EcPAP) revealed that the shape and size of the nucleobase-interacting pocket of EcPAP are maintained by an intra-molecular hydrogen-network, making it suitable for the accommodation of only ATP, using a single amino acid, Arg(197). The pocket structure is sustained by interactions between the catalytic domain and the RNA-binding domain. EcPAP has a flexible basic C-terminal region that contributes to optimal RNA translocation for processive adenosine 5'-monophosphate (AMP) incorporations onto the 3'-end of RNAs. A comparison of the EcPAP structure with those of other template-independent RNA polymerases suggests that structural changes of domain(s) outside the conserved catalytic core domain altered the substrate specificities of the template-independent RNA polymerases.

Mechanism for the alteration of the substrate specificities of template-independent RNA polymerases.,Toh Y, Takeshita D, Nagaike T, Numata T, Tomita K Structure. 2011 Feb 9;19(2):232-43. PMID:21300291<ref>PMID:21300291</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 3aqn" style="background-color:#fffaf0;"></div>

==See Also==
*[[Poly(A) polymerase 3D structures|Poly(A) polymerase 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Escherichia coli DH1]]
[[Category: Large Structures]]
[[Category: Takeshita D]]
[[Category: Toh Y]]
[[Category: Tomita K]]