3rf2

<StructureSection load='3rf2' size='340' side='right' caption='[[3rf2]], [[Resolution|resolution]] 2.16&Aring;' scene=''>

<table><tr><td colspan='2'>[[3rf2]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/"aquifex_aeolicus"_huber_and_stetter_2001 "aquifex aeolicus" huber and stetter 2001]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3RF2 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3RF2 FirstGlance]. <br>

</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene></td></tr>

<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">rpsH, aq_1651 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=63363 "Aquifex aeolicus" Huber and Stetter 2001])</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=3rf2 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3rf2 OCA], [http://pdbe.org/3rf2 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=3rf2 RCSB], [http://www.ebi.ac.uk/pdbsum/3rf2 PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=3rf2 ProSAT]</span></td></tr>

[[http://www.uniprot.org/uniprot/RS8_AQUAE RS8_AQUAE]] One of the primary rRNA binding proteins, it binds directly to 16S rRNA central domain where it helps coordinate assembly of the platform of the 30S subunit (By similarity).

The assembly of ribonucleoprotein complexes occurs under a broad range of conditions, but the principles that promote assembly and allow function at high temperature are poorly understood. The ribosomal protein S8 from Aquifex aeolicus (AS8) is unique in that there is a 41-residue insertion in the consensus S8 sequence. In addition, AS8 exhibits an unusually high affinity for the 16S ribosomal RNA, characterized by a picomolar dissociation constant that is approximately 26,000-fold tighter than the equivalent interaction from Escherichia coli. Deletion analysis demonstrated that binding to the minimal site on helix 21 occurred at the same nanomolar affinity found for other bacterial species. The additional affinity required the presence of a three-helix junction between helices 20, 21, and 22. The crystal structure of AS8, revealing the helix-loop-helix geometry of the unique AS8 insertion region, was solved, while the core of the molecule was conserved with known S8 structures. The AS8 structure was modeled onto the structure of the 30S ribosomal subunit from E. coli, suggesting the possibility that the unique subdomain provides additional backbone and side-chain contacts between the protein and an unpaired base within the three-way junction of helices 20, 21, and 22. Point mutations in the protein insertion subdomain resulted in a significantly reduced RNA binding affinity with respect to wild-type AS8. These results indicate that the AS8-specific subdomain provides additional interactions with the three-way junction that contribute to the extremely tight binding to ribosomal RNA.

 

<div class="pdbe-citations 3rf2" style="background-color:#fffaf0;"></div>

== References ==

[[Category: Aquifex aeolicus huber and stetter 2001]]

[[Category: Menichelli, E]]

[[Category: Williamson, J R]]

[[Category: Hyperthermophilic bacterium]]

[[Category: Ribosomal protein]]

[[Category: Ribosome]]

[[Category: Rna-binding protein]]