View source for 3zzl


==Bacillus halodurans trp RNA-binding attenuation protein (TRAP): a 12- subunit assembly==
<StructureSection load='3zzl' size='340' side='right'caption='[[3zzl]], [[Resolution|resolution]] 1.67&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[3zzl]] is a 3 chain structure with sequence from [https://en.wikipedia.org/wiki/Alkalihalobacillus_halodurans Alkalihalobacillus halodurans]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3ZZL OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=3ZZL 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]] 1.67&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=TRP:TRYPTOPHAN'>TRP</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=3zzl FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3zzl OCA], [https://pdbe.org/3zzl PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=3zzl RCSB], [https://www.ebi.ac.uk/pdbsum/3zzl PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=3zzl ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/MTRB_HALH5 MTRB_HALH5] Required for transcription attenuation control in the Trp operon. This trans-acting factor seems to recognize a 10 bases nucleotide sequence in the Trp leader transcript causing transcription termination. Binds the leader RNA only in presence of L-tryptophan (By similarity).
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== Publication Abstract from PubMed ==
BACKGROUND: Many critical cellular functions are performed by multisubunit circular protein oligomers whose internal geometry has evolved to meet functional requirements. The subunit number is arguably the most critical parameter of a circular protein assembly, affecting the internal and external diameters of the assembly and often impacting on the protein's function. Although accurate structural information has been obtained for several circular proteins, a lack of accurate information on alternative oligomeric states has prevented engineering such transitions. In this study we used the bacterial transcription regulator TRAP as a model system to investigate the features that define the oligomeric state of a circular protein and to question how the subunit number could be manipulated. METHODOLOGY/PRINCIPAL FINDINGS: We find that while Bacillus subtilis and Bacillus stearothermophilus TRAP form 11-subunit oligomers, the Bacillus halodurans TRAP exclusively forms 12-subunit assemblies. Significantly, the two states of TRAP are related by a simple rigid body rotation of individual subunits around inter-subunit axes. We tested if such a rotation could be induced by insertion or deletion mutations at the subunit interface. Using wild type 11-subunit TRAP, we demonstrate that removal of five C-terminal residues at the outer side of the inter-subunit axis or extension of an amino acid side chain at the opposite, inner side, increased the subunit number from 11 to 12. Our findings are supported by crystal structures of TRAP oligomers and by native mass spectrometry data. CONCLUSIONS/SIGNIFICANCE: The subunit number of the TRAP oligomer can be manipulated by introducing deletion or addition mutations at the subunit interface. An analysis of available and emerging structural data on alternative oligomeric states indicates that the same principles may also apply to the subunit number of other circular assemblies suggesting that the deletion/addition approach could be used generally to engineer transitions between different oligomeric states.

How to Change the Oligomeric State of a Circular Protein Assembly: Switch from 11-Subunit to 12-Subunit TRAP Suggests a General Mechanism.,Chen CS, Smits C, Dodson GG, Shevtsov MB, Merlino N, Gollnick P, Antson AA PLoS One. 2011;6(10):e25296. Epub 2011 Oct 3. PMID:21984911<ref>PMID:21984911</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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==See Also==
*[[Tryptophan RNA-binding attenuation protein|Tryptophan RNA-binding attenuation protein]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Alkalihalobacillus halodurans]]
[[Category: Large Structures]]
[[Category: Antson AA]]
[[Category: Chen C]]
[[Category: Dodson GG]]
[[Category: Gollnick P]]
[[Category: Merlino N]]
[[Category: Shevtsov MB]]
[[Category: Smits C]]