View source for 8qlk


==Crystal structure of the pneumococcal Substrate-binding protein AliB in complex with Peptide 2==
<StructureSection load='8qlk' size='340' side='right'caption='[[8qlk]], [[Resolution|resolution]] 2.29&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[8qlk]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Streptococcus_pneumoniae Streptococcus pneumoniae] 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=8QLK OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=8QLK 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]] 2.29&#8491;</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=8qlk FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=8qlk OCA], [https://pdbe.org/8qlk PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=8qlk RCSB], [https://www.ebi.ac.uk/pdbsum/8qlk PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=8qlk ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/ALIB_STRR6 ALIB_STRR6] Part of the binding-protein-dependent transport system for oligopeptides; probably an oligopeptide binding protein.
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
ATP-binding cassette (ABC) transport systems are crucial for bacteria to ensure sufficient uptake of nutrients that are not produced de novo or improve the energy balance. The cell surface of the pathobiont Streptococcus pneumoniae (pneumococcus) is decorated with a substantial array of ABC transporters, critically influencing nasopharyngeal colonization and invasive infections. Given the auxotrophic nature of pneumococci for certain amino acids, the Ami ABC transporter system, orchestrating oligopeptide uptake, becomes indispensable in host compartments lacking amino acids. The system comprises five exposed Oligopeptide Binding Proteins (OBPs) and four proteins building the ABC transporter channel. Here, we present a structural analysis of all the OBPs in this system. Multiple crystallographic structures, capturing both open and closed conformations along with complexes involving chemically synthesized peptides, have been solved at high resolution providing insights into the molecular basis of their diverse peptide specificities. Mass spectrometry analysis of oligopeptides demonstrates the unexpected remarkable promiscuity of some of these proteins when expressed in Escherichia coli, displaying affinity for a wide range of peptides. Finally, a model is proposed for the complete Ami transport system in complex with its various OBPs. We further disclosed, through in silico modelling, some essential structural changes facilitating oligopeptide transport into the cellular cytoplasm. Thus, the structural analysis of the Ami system provides valuable insights into the mechanism and specificity of oligopeptide binding by the different OBPs, shedding light on the intricacies of the uptake mechanism and the in vivo implications for this human pathogen.

Molecular and structural basis of oligopeptide recognition by the Ami transporter system in pneumococci.,Alcorlo M, Abdullah MR, Steil L, Sotomayor F, Lopez-de Oro L, de Castro S, Velazquez S, Kohler TP, Jimenez E, Medina A, Uson I, Keller LE, Bradshaw JL, McDaniel LS, Camarasa MJ, Volker U, Hammerschmidt S, Hermoso JA PLoS Pathog. 2024 Jun 5;20(6):e1011883. doi: 10.1371/journal.ppat.1011883. , eCollection 2024 Jun. PMID:38838057<ref>PMID:38838057</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 8qlk" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Streptococcus pneumoniae]]
[[Category: Synthetic construct]]
[[Category: Abdullah MR]]
[[Category: Alcorlo M]]
[[Category: Hammerschmidt S]]
[[Category: Hermoso J]]