View source for 6buw


==Thermus thermophilus 70S complex containing 16S G299A ram mutation and empty A site.==
<StructureSection load='6buw' size='340' side='right'caption='[[6buw]], [[Resolution|resolution]] 3.50&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[6buw]] is a 20 chain structure with sequence from [https://en.wikipedia.org/wiki/Thermus_thermophilus_HB8 Thermus thermophilus HB8]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6BUW OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=6BUW 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]] 3.5&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</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=6buw FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6buw OCA], [https://pdbe.org/6buw PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=6buw RCSB], [https://www.ebi.ac.uk/pdbsum/6buw PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=6buw ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/RS2_THET8 RS2_THET8] Spans the head-body hinge region of the 30S subunit. Is loosely associated with the 30S subunit.[HAMAP-Rule:MF_00291_B]
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Decoding is thought to be governed by a conformational transition in the ribosome-open (off) to closed (on)-that occurs upon codon-anticodon pairing in the A site. Ribosomal ambiguity (ram) mutations increase miscoding and map to disparate regions, consistent with a role for ribosome dynamics in decoding, yet precisely how these mutations act has been unclear. Here, we solved crystal structures of 70S ribosomes harboring 16S ram mutations G299A and G347U in the absence A-site tRNA (A-tRNA) and in the presence of a near-cognate anticodon stem-loop (ASL). In the absence of an A-tRNA, each of the mutant ribosomes exhibits a partially closed (on) state. In the 70S-G347U structure, the 30S shoulder is rotated inward and intersubunit bridge B8 is disrupted. In the 70S-G299A structure, the 30S shoulder is rotated inward and decoding nucleotide G530 flips into the anti conformation. Both of these mutant ribosomes adopt the fully closed (on) conformation in the presence of near-cognate A-tRNA, just as they do with cognate A-tRNA. Thus, these ram mutations act by promoting the open (off) to closed (on) transition, albeit in somewhat distinct ways. This work reveals the functional importance of 30S shoulder rotation for productive aminoacylated-tRNA incorporation.

Ribosomal ambiguity (ram) mutations promote the open (off) to closed (on) transition and thereby increase miscoding.,Hoffer ED, Maehigashi T, Fredrick K, Dunham CM Nucleic Acids Res. 2018 Nov 22. pii: 5198528. doi: 10.1093/nar/gky1178. PMID:30476222<ref>PMID:30476222</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 6buw" style="background-color:#fffaf0;"></div>

==See Also==
*[[Ribosomal protein THX 3D structures|Ribosomal protein THX 3D structures]]
*[[Ribosome 3D structures|Ribosome 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Thermus thermophilus HB8]]
[[Category: Dunham CM]]
[[Category: Fagan CE]]
[[Category: Hoffer ED]]
[[Category: Maehigashi T]]