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4y2n
From Proteopedia
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| - | '''Unreleased structure''' | ||
| - | + | ==Structure of CFA/I pili major subunit CfaB trimer== | |
| + | <StructureSection load='4y2n' size='340' side='right'caption='[[4y2n]], [[Resolution|resolution]] 2.40Å' scene=''> | ||
| + | == Structural highlights == | ||
| + | <table><tr><td colspan='2'>[[4y2n]] is a 3 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_coli_ETEC_H10407 Escherichia coli ETEC H10407]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4Y2N OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4Y2N 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]] 2.4Å</td></tr> | ||
| + | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=EDO:1,2-ETHANEDIOL'>EDO</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</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=4y2n FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4y2n OCA], [https://pdbe.org/4y2n PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4y2n RCSB], [https://www.ebi.ac.uk/pdbsum/4y2n PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4y2n ProSAT]</span></td></tr> | ||
| + | </table> | ||
| + | == Function == | ||
| + | [https://www.uniprot.org/uniprot/FMC1_ECOH1 FMC1_ECOH1] Fimbriae (also called pili), polar filaments radiating from the surface of the bacterium to a length of 0.5-1.5 micrometers and numbering 100-300 per cell, enable bacteria to colonize the epithelium of specific host organs. | ||
| + | <div style="background-color:#fffaf0;"> | ||
| + | == Publication Abstract from PubMed == | ||
| + | The assembly of the class 5 colonization factor antigen I (CFA/I) fimbriae of enterotoxigenic E. coli was proposed to proceed via the alternate chaperone-usher pathway. Here, we show that in the absence of the chaperone CfaA, CfaB, the major pilin subunit of CFA/I fimbriae, is able to spontaneously refold and polymerize into cyclic trimers. CfaA kinetically traps CfaB to form a metastable complex that can be stabilized by mutations. Crystal structure of the stabilized complex reveals distinctive interactions provided by CfaA to trap CfaB in an assembly competent state through donor-strand complementation (DSC) and cleft-mediated anchorage. Mutagenesis indicated that DSC controls the stability of the chaperone-subunit complex and the cleft-mediated anchorage of the subunit C-terminus additionally assist in subunit refolding. Surprisingly, over-stabilization of the chaperone-subunit complex led to delayed fimbria assembly, whereas destabilizing the complex resulted in no fimbriation. Thus, CfaA acts predominantly as a kinetic trap by stabilizing subunit to avoid its off-pathway self-polymerization that results in energetically favorable trimers and could serve as a driving force for CFA/I pilus assembly, representing an energetic landscape unique to class 5 fimbria assembly. | ||
| - | + | Off-pathway assembly of fimbria subunits is prevented by chaperone CfaA of CFA/I fimbriae from enterotoxigenic E. coli.,Bao R, Liu Y, Savarino SJ, Xia D Mol Microbiol. 2016 Dec;102(6):975-991. doi: 10.1111/mmi.13530. Epub 2016 Oct 7. PMID:27627030<ref>PMID:27627030</ref> | |
| - | + | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |
| - | [[Category: | + | </div> |
| - | [[Category: Bao | + | <div class="pdbe-citations 4y2n" style="background-color:#fffaf0;"></div> |
| - | [[Category: Xia | + | |
| + | ==See Also== | ||
| + | *[[Colonization factor antigen|Colonization factor antigen]] | ||
| + | *[[Pilin 3D structures|Pilin 3D structures]] | ||
| + | == References == | ||
| + | <references/> | ||
| + | __TOC__ | ||
| + | </StructureSection> | ||
| + | [[Category: Escherichia coli ETEC H10407]] | ||
| + | [[Category: Large Structures]] | ||
| + | [[Category: Bao R]] | ||
| + | [[Category: Xia D]] | ||
Current revision
Structure of CFA/I pili major subunit CfaB trimer
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