4aw8

==X-ray structure of zinc bound protein ZinT from Salmonella enterica==

<StructureSection load='4aw8' size='340' side='right' caption='[[4aw8]], [[Resolution|resolution]] 2.00&Aring;' scene=''>

<table><tr><td colspan='2'>[[4aw8]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/Salmonella_enterica_subsp._enterica_serovar_4,5,12:i:-_str._cvm23701 Salmonella enterica subsp. enterica serovar 4,5,12:i:- str. cvm23701]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4AW8 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4AW8 FirstGlance]. <br>

</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=NA:SODIUM+ION'>NA</scene>, <scene name='pdbligand=PG6:1-(2-METHOXY-ETHOXY)-2-{2-[2-(2-METHOXY-ETHOXY]-ETHOXY}-ETHANE'>PG6</scene>, <scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</scene></td></tr>

<tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[4arh|4arh]]</td></tr>

<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4aw8 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4aw8 OCA], [http://www.rcsb.org/pdb/explore.do?structureId=4aw8 RCSB], [http://www.ebi.ac.uk/pdbsum/4aw8 PDBsum]</span></td></tr>

<div style="background-color:#fffaf0;">

== Publication Abstract from PubMed ==

BACKGROUND: In Gram-negative bacteria the ZnuABC transporter ensures adequate zinc import in Zn(II)-poor environments, like those encountered by pathogens within the infected host. Recently, the metal-binding protein ZinT was suggested to operate as an accessory component of ZnuABC in periplasmic zinc recruitment. Since ZinT is known to form a ZinT-ZnuA complex in the presence of Zn(II) it was proposed to transfer Zn(II) to ZnuA. The present work was undertaken to test this claim. METHODS: ZinT and its structural relationship with ZnuA have been characterized by multiple biophysical techniques (X-ray crystallography, SAXS, analytical ultracentrifugation, fluorescence spectroscopy). RESULTS: The metal-free and metal-bound crystal structures of Salmonella enterica ZinT show one Zn(II) binding site and limited structural changes upon metal removal. Spectroscopic titrations with Zn(II) yield a KD value of 22+/-2nM for ZinT, while those with ZnuA point to one high affinity (KD&lt;20nM) and one low affinity Zn(II) binding site (KD in the micromolar range). Sedimentation velocity experiments established that Zn(II)-bound ZinT interacts with ZnuA, whereas apo-ZinT does not. The model of the ZinT-ZnuA complex derived from small angle X-ray scattering experiments points to a disposition that favors metal transfer as the metal binding cavities of the two proteins face each other. CONCLUSIONS: ZinT acts as a Zn(II)-buffering protein that delivers Zn(II) to ZnuA. GENERAL SIGNIFICANCE: Knowledge of the ZinT-ZnuA relationship is crucial for understanding bacterial Zn(II) uptake.

 

The Salmonella enterica ZinT structure, zinc affinity and interaction with the high-affinity uptake protein ZnuA provide insight into the management of periplasmic zinc.,Ilari A, Alaleona F, Tria G, Petrarca P, Battistoni A, Zamparelli C, Verzili D, Falconi M, Chiancone E Biochim Biophys Acta. 2014 Jan;1840(1):535-44. doi: 10.1016/j.bbagen.2013.10.010., Epub 2013 Oct 12. PMID:24128931<ref>PMID:24128931</ref>

 

<references/>

[[Category: Salmonella enterica subsp. enterica serovar 4,5,12:i:- str. cvm23701]]

[[Category: Alaleona, F]]

[[Category: Battistoni, A]]

[[Category: Chiancone, E]]

[[Category: Ilari, A]]

[[Category: Petrarca, P]]

[[Category: Zinc transport]]