View source for 4ryq


==Crystal structure of BcTSPO, type 2 at 1.7 Angstrom==
<StructureSection load='4ryq' size='340' side='right'caption='[[4ryq]], [[Resolution|resolution]] 1.70&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[4ryq]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Bacillus_cereus_ATCC_14579 Bacillus cereus ATCC 14579]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4RYQ OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4RYQ 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]] 1.7&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=MPG:[(Z)-OCTADEC-9-ENYL]+(2R)-2,3-BIS(OXIDANYL)PROPANOATE'>MPG</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=4ryq FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4ryq OCA], [https://pdbe.org/4ryq PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4ryq RCSB], [https://www.ebi.ac.uk/pdbsum/4ryq PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4ryq ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/TSPO_BACCR TSPO_BACCR] Binds tetrapyrroles and promotes the photooxidative degradation of protoporphyrin IX (PubMed:25635100). Can bind the benzodiazepine receptor agonist PK-11195 (in vitro); this interferes with photooxidative tetrapyrrole degradation (PubMed:25635100). May play a role in the transmembrane transport of tetrapyrroles and similar compounds (By similarity).[UniProtKB:Q9RFC8]<ref>PMID:25635100</ref> 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Translocator proteins (TSPOs) bind steroids and porphyrins, and they are implicated in many human diseases, for which they serve as biomarkers and therapeutic targets. TSPOs have tryptophan-rich sequences that are highly conserved from bacteria to mammals. Here we report crystal structures for Bacillus cereus TSPO (BcTSPO) down to 1.7 A resolution, including a complex with the benzodiazepine-like inhibitor PK11195. We also describe BcTSPO-mediated protoporphyrin IX (PpIX) reactions, including catalytic degradation to a previously undescribed heme derivative. We used structure-inspired mutations to investigate reaction mechanisms, and we showed that TSPOs from Xenopus and man have similar PpIX-directed activities. Although TSPOs have been regarded as transporters, the catalytic activity in PpIX degradation suggests physiological importance for TSPOs in protection against oxidative stress.

Protein structure. Structure and activity of tryptophan-rich TSPO proteins.,Guo Y, Kalathur RC, Liu Q, Kloss B, Bruni R, Ginter C, Kloppmann E, Rost B, Hendrickson WA Science. 2015 Jan 30;347(6221):551-5. doi: 10.1126/science.aaa1534. PMID:25635100<ref>PMID:25635100</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 4ryq" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Bacillus cereus ATCC 14579]]
[[Category: Large Structures]]
[[Category: Guo Y]]
[[Category: Hendrickson WA]]
[[Category: Liu Q]]