3e5f

<StructureSection load='3e5f' size='340' side='right' caption='[[3e5f]], [[Resolution|resolution]] 2.70&Aring;' scene=''>

<table><tr><td colspan='2'>[[3e5f]] is a 1 chain structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3E5F OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3E5F FirstGlance]. <br>

</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=EEM:[(3S)-3-AMINO-4-HYDROXY-4-OXO-BUTYL]-[[(2S,3S,4R,5R)-5-(6-AMINOPURIN-9-YL)-3,4-DIHYDROXY-OXOLAN-2-YL]METHYL]-METHYL-SELANIUM'>EEM</scene>, <scene name='pdbligand=SR:STRONTIUM+ION'>SR</scene></td></tr>

<tr id='NonStdRes'><td class="sblockLbl"><b>[[Non-Standard_Residue|NonStd Res:]]</b></td><td class="sblockDat"><scene name='pdbligand=GTP:GUANOSINE-5-TRIPHOSPHATE'>GTP</scene></td></tr>

<tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[3e5c|3e5c]], [[3e5e|3e5e]]</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=3e5f FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3e5f OCA], [http://www.rcsb.org/pdb/explore.do?structureId=3e5f RCSB], [http://www.ebi.ac.uk/pdbsum/3e5f PDBsum]</span></td></tr>

<div style="background-color:#fffaf0;">

== Publication Abstract from PubMed ==

Three distinct classes of S-adenosyl-L-methionine (SAM)-responsive riboswitches have been identified that regulate bacterial gene expression at the levels of transcription attenuation or translation inhibition. The S(MK) box (SAM-III) translational riboswitch has been identified in the SAM synthetase gene in members of the Lactobacillales. Here we report the 2.2-A crystal structure of the Enterococcus faecalis S(MK) box riboswitch. The Y-shaped riboswitch organizes its conserved nucleotides around a three-way junction for SAM recognition. The Shine-Dalgarno sequence, which is sequestered by base-pairing with the anti-Shine-Dalgarno sequence in response to SAM binding, also directly participates in SAM recognition. The riboswitch makes extensive interactions with the adenosine and sulfonium moieties of SAM but does not appear to recognize the tail of the methionine moiety. We captured a structural snapshot of the S(MK) box riboswitch sampling the near-cognate ligand S-adenosyl-L-homocysteine (SAH) in which SAH was found to adopt an alternative conformation and fails to make several key interactions.

Crystal structures of the SAM-III/S(MK) riboswitch reveal the SAM-dependent translation inhibition mechanism.,Lu C, Smith AM, Fuchs RT, Ding F, Rajashankar K, Henkin TM, Ke A Nat Struct Mol Biol. 2008 Oct;15(10):1076-83. Epub 2008 Sep 21. PMID:18806797<ref>PMID:18806797</ref>

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

</div>

*[[Riboswitch|Riboswitch]]

[[Category: Lu, C]]

[[Category: Rna]]

[[Category: Smk sam riboswitch shine-delgarno translation regulation]]