View source for 7qha


==Cryo-EM structure of the Tripartite ATP-independent Periplasmic (TRAP) transporter SiaQM from Photobacterium profundum in amphipol==
<StructureSection load='7qha' size='340' side='right'caption='[[7qha]], [[Resolution|resolution]] 2.97&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[7qha]] is a 3 chain structure with sequence from [https://en.wikipedia.org/wiki/Helicobacter_pylori Helicobacter pylori], [https://en.wikipedia.org/wiki/Photobacterium_profundum_SS9 Photobacterium profundum SS9] and [https://en.wikipedia.org/wiki/Synthetic_construct Synthetic construct]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=7QHA OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=7QHA FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Electron Microscopy, [[Resolution|Resolution]] 2.97&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=NA:SODIUM+ION'>NA</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=7qha FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=7qha OCA], [https://pdbe.org/7qha PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=7qha RCSB], [https://www.ebi.ac.uk/pdbsum/7qha PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=7qha ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/Q6LPW0_PHOPR Q6LPW0_PHOPR] Part of the tripartite ATP-independent periplasmic (TRAP) transport system.[RuleBase:RU369079]
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== Publication Abstract from PubMed ==
In bacteria and archaea, tripartite ATP-independent periplasmic (TRAP) transporters uptake essential nutrients. TRAP transporters receive their substrates via a secreted soluble substrate-binding protein. How a sodium ion-driven secondary active transporter is strictly coupled to a substrate-binding protein is poorly understood. Here we report the cryo-EM structure of the sialic acid TRAP transporter SiaQM from Photobacterium profundum at 2.97 A resolution. SiaM comprises a "transport" domain and a "scaffold" domain, with the transport domain consisting of helical hairpins as seen in the sodium ion-coupled elevator transporter VcINDY. The SiaQ protein forms intimate contacts with SiaM to extend the size of the scaffold domain, suggesting that TRAP transporters may operate as monomers, rather than the typically observed oligomers for elevator-type transporters. We identify the Na(+) and sialic acid binding sites in SiaM and demonstrate a strict dependence on the substrate-binding protein SiaP for uptake. We report the SiaP crystal structure that, together with docking studies, suggest the molecular basis for how sialic acid is delivered to the SiaQM transporter complex. We thus propose a model for substrate transport by TRAP proteins, which we describe herein as an 'elevator-with-an-operator' mechanism.

Structure and mechanism of a tripartite ATP-independent periplasmic TRAP transporter.,Davies JS, Currie MJ, North RA, Scalise M, Wright JD, Copping JM, Remus DM, Gulati A, Morado DR, Jamieson SA, Newton-Vesty MC, Abeysekera GS, Ramaswamy S, Friemann R, Wakatsuki S, Allison JR, Indiveri C, Drew D, Mace PD, Dobson RCJ Nat Commun. 2023 Feb 27;14(1):1120. doi: 10.1038/s41467-023-36590-1. PMID:36849793<ref>PMID:36849793</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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<div class="pdbe-citations 7qha" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Helicobacter pylori]]
[[Category: Large Structures]]
[[Category: Photobacterium profundum SS9]]
[[Category: Synthetic construct]]
[[Category: Davies JS]]
[[Category: Dobson RCJ]]
[[Category: Morado D]]
[[Category: North RA]]