5vjb

<table><tr><td colspan='2'>[[5vjb]] is a 4 chain structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5VJB OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=5VJB FirstGlance]. <br>

</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=GAI:GUANIDINE'>GAI</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=SPM:SPERMINE'>SPM</scene></td></tr>

<tr id='NonStdRes'><td class="sblockLbl"><b>[[Non-Standard_Residue|NonStd Res:]]</b></td><td class="sblockDat"><scene name='pdbligand=5BU:5-BROMO-URIDINE-5-MONOPHOSPHATE'>5BU</scene></td></tr>

<tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[5vj9|5vj9]]</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=5vjb FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5vjb OCA], [http://pdbe.org/5vjb PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=5vjb RCSB], [http://www.ebi.ac.uk/pdbsum/5vjb PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=5vjb ProSAT]</span></td></tr>

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== Publication Abstract from PubMed ==

The guanidine-II riboswitch, also known as mini-ykkC, is a conserved mRNA element with more than 800 examples in bacteria. It consists of two stem-loops capped by identical, conserved tetraloops that are separated by a linker region of variable length and sequence. Like the guanidine-I riboswitch, it controls the expression of guanidine carboxylases and SugE-like genes. The guanidine-II riboswitch specifically binds free guanidinium cations and functions as a translationally controlled on-switch. Here we report the structure of a P2 stem-loop from the Pseudomonas aeruginosa guanidine-II riboswitch aptamer bound to guanidine at 1.57 A resolution. The hairpins dimerize via the conserved tetraloop, which also contains the binding pocket. Two guanidinium molecules bind near the dimerization interface, one in each tetraloop. The guanidinium cation is engaged in extensive hydrogen bonding to the RNA. Contacts include the Hoogsteen face of a guanine base and three nonbridging phosphate oxygens. Cation-pi interactions and ionic interactions also stabilize ligand binding. The guanidine-II riboswitch utilizes the same recognition strategies as the guanidine-I riboswitch while adopting an entirely different and much smaller RNA fold.

Structural basis for ligand binding to the guanidine-II riboswitch.,Reiss CW, Strobel SA RNA. 2017 Sep;23(9):1338-1343. doi: 10.1261/rna.061804.117. Epub 2017 Jun 9. PMID:28600356<ref>PMID:28600356</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>

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<div class="pdbe-citations 5vjb" style="background-color:#fffaf0;"></div>

== References ==

<references/>

[[Category: Reiss, C W]]

[[Category: Strobel, S A]]

[[Category: Guanidine]]

[[Category: Rna]]