3ph0: Difference between revisions
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[[ | ==Crystal structure of the heteromolecular chaperone, AscE-AscG, from the type III secretion system in Aeromonas hydrophila== | ||
<StructureSection load='3ph0' size='340' side='right' caption='[[3ph0]], [[Resolution|resolution]] 2.40Å' scene=''> | |||
== Structural highlights == | |||
<table><tr><td colspan='2'>[[3ph0]] is a 4 chain structure with sequence from [http://en.wikipedia.org/wiki/Aeromonas_hydrophila Aeromonas hydrophila]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3PH0 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3PH0 FirstGlance]. <br> | |||
</td></tr><tr><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3ph0 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3ph0 OCA], [http://www.rcsb.org/pdb/explore.do?structureId=3ph0 RCSB], [http://www.ebi.ac.uk/pdbsum/3ph0 PDBsum]</span></td></tr> | |||
<table> | |||
<div style="background-color:#fffaf0;"> | |||
== Publication Abstract from PubMed == | |||
BACKGROUND: The putative needle complex subunit AscF forms a ternary complex with the chaperones AscE and AscG in the type III secretion system of Aeromonas hydrophila so as to avoid premature assembly. Previously, we demonstrated that the C-terminal region of AscG (residues 62-116) in the hetero-molecular chaperone, AscE-AscG, is disordered and susceptible to limited protease digestion. METHODOLOGY/PRINCIPAL FINDINGS: Here, we report the crystal structure of the ordered AscG(1-61) region in complex with AscE at 2.4 A resolution. Helices alpha2 and alpha3 of AscE in the AscE-AscG(1-61) complex assumes a helix-turn-helix conformation in an anti-parallel fashion similar to that in apo AscE. However, in the presence of AscG, an additional N-terminal helix alpha1 in AscE (residues 4-12) is observed. PscG or YscG in the crystal structures of PscE-PscF-PscG or YscE-YscF-YscG, respectively, assumes a typical tetratricopeptide repeat (TPR) fold with three TPR repeats and one C-terminal capping helix. By comparison, AscG in AscE-AscG(1-61) comprises three anti-parallel helices that resembles the N-terminal TPR repeats in the corresponding region of PscG or YscG in PscE-PscF-PscG or YscE-YscF-YscG. Thermal denaturation of AscE-AscG and AscE-AscG(1-61) complexes demonstrates that the C-terminal disordered region does not contribute to the thermal stability of the overall complex. CONCLUSION/SIGNIFICANCE: The N-terminal region of the AscG in the AscE-AscG complex is ordered and assumes a structure similar to those in the corresponding regions of PscE-PscG-PscF or YscE-YscF-YscG complexes. While the C-terminal region of AscG in the AscE-AscG complex is disordered and will assume its structure only in the presence of the substrate AscF. We hypothesize that AscE act as a chaperone of the chaperone to keep AscG in a stable but partially disordered state for interaction with AscF. | |||
Crystal structure of the heteromolecular chaperone, AscE-AscG, from the type III secretion system in Aeromonas hydrophila.,Chatterjee C, Kumar S, Chakraborty S, Tan YW, Leung KY, Sivaraman J, Mok YK PLoS One. 2011 Apr 29;6(4):e19208. PMID:21559439<ref>PMID:21559439</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
</div> | |||
== References == | |||
<references/> | |||
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</StructureSection> | |||
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[[Category: Aeromonas hydrophila]] | [[Category: Aeromonas hydrophila]] | ||
[[Category: Chakraborty, S.]] | [[Category: Chakraborty, S.]] | ||