View source for 3f85


==Structure of fusion complex of homo trimeric major pilin subunits CfaB of CFA/I fimbirae from ETEC E. coli==
<StructureSection load='3f85' size='340' side='right'caption='[[3f85]], [[Resolution|resolution]] 2.10&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[3f85]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3F85 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=3F85 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]] 2.1&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><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=3f85 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3f85 OCA], [https://pdbe.org/3f85 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=3f85 RCSB], [https://www.ebi.ac.uk/pdbsum/3f85 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=3f85 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.
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== Publication Abstract from PubMed ==
Adhesion pili (fimbriae) play a critical role in initiating the events that lead to intestinal colonization and diarrheal disease by enterotoxigenic Escherichia coli (ETEC), an E. coli pathotype that inflicts an enormous global disease burden. We elucidate atomic structures of an ETEC major pilin subunit, CfaB, from colonization factor antigen I (CFA/I) fimbriae. These data are used to construct models for 2 morphological forms of CFA/I fimbriae that are both observed in vivo: the helical filament into which it is typically assembled, and an extended, unwound conformation. Modeling and corroborative mutational data indicate that proline isomerization is involved in the conversion between these helical and extended forms. Our findings affirm the strong structural similarities seen between class 5 fimbriae (from bacteria primarily causing gastrointestinal disease) and class 1 pili (from bacteria that cause urinary, respiratory, and other infections) in the absence of significant primary sequence similarity. They also suggest that morphological and biochemical differences between fimbrial types, regardless of class, provide structural specialization that facilitates survival of each bacterial pathotype in its preferred host microenvironment. Last, we present structural evidence for bacterial use of antigenic variation to evade host immune responses, in that residues occupying the predicted surface-exposed face of CfaB and related class 5 pilins show much higher genetic sequence variability than the remainder of the pilin protein.

Structure of CFA/I fimbriae from enterotoxigenic Escherichia coli.,Li YF, Poole S, Nishio K, Jang K, Rasulova F, McVeigh A, Savarino SJ, Xia D, Bullitt E Proc Natl Acad Sci U S A. 2009 Jun 30;106(26):10793-8. Epub 2009 Jun 10. PMID:19515814<ref>PMID:19515814</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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<div class="pdbe-citations 3f85" style="background-color:#fffaf0;"></div>

==See Also==
*[[Colonization factor antigen|Colonization factor antigen]]
*[[Pilin 3D structures|Pilin 3D structures]]
== References ==
<references/>
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</StructureSection>
[[Category: Escherichia coli]]
[[Category: Large Structures]]
[[Category: Li YF]]
[[Category: Xia D]]