View source for 7ofw


==Nontypeable Haemophillus influenzae SapA in complex with heme==
<StructureSection load='7ofw' size='340' side='right'caption='[[7ofw]], [[Resolution|resolution]] 3.15&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[7ofw]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli] and [https://en.wikipedia.org/wiki/Haemophilus_influenzae_86-028NP Haemophilus influenzae 86-028NP]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=7OFW OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=7OFW 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]] 3.15&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=HEM:PROTOPORPHYRIN+IX+CONTAINING+FE'>HEM</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=7ofw FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=7ofw OCA], [https://pdbe.org/7ofw PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=7ofw RCSB], [https://www.ebi.ac.uk/pdbsum/7ofw PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=7ofw ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/Q4QL73_HAEI8 Q4QL73_HAEI8] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Nontypeable Haemophilus influenzae (NTHi) is a significant pathogen in respiratory disease and otitis media. Important for NTHi survival, colonization and persistence in vivo is the Sap (sensitivity to antimicrobial peptides) ABC transporter system. Current models propose a direct role for Sap in heme and antimicrobial peptide (AMP) transport. Here, the crystal structure of SapA, the periplasmic component of Sap, in a closed, ligand bound conformation, is presented. Phylogenetic and cavity volume analysis predicts that the small, hydrophobic SapA central ligand binding cavity is most likely occupied by a hydrophobic di- or tri- peptide. The cavity is of insufficient volume to accommodate heme or folded AMPs. Crystal structures of SapA have identified surface interactions with heme and dsRNA. Heme binds SapA weakly (Kd 282 muM) through a surface exposed histidine, while the dsRNA is coordinated via residues which constitute part of a conserved motif (estimated Kd 4.4 muM). The RNA affinity falls within the range observed for characterized RNA/protein complexes. Overall, we describe in molecular-detail the interactions of SapA with heme and dsRNA and propose a role for SapA in the transport of di- or tri-peptides.

The structure of nontypeable Haemophilus influenzae SapA in a closed conformation reveals a constricted ligand-binding cavity and a novel RNA binding motif.,Lukacik P, Owen CD, Harris G, Bolla JR, Picaud S, Alibay I, Nettleship JE, Bird LE, Owens RJ, Biggin PC, Filippakopoulos P, Robinson CV, Walsh MA PLoS One. 2021 Oct 15;16(10):e0256070. doi: 10.1371/journal.pone.0256070. , eCollection 2021. PMID:34653190<ref>PMID:34653190</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 7ofw" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Escherichia coli]]
[[Category: Haemophilus influenzae 86-028NP]]
[[Category: Large Structures]]
[[Category: Bird LE]]
[[Category: Lukacik P]]
[[Category: Nettleship JE]]
[[Category: Owen CD]]
[[Category: Owens RJ]]
[[Category: Walsh MA]]