View source for 4q8d


==Crystal structure of a macrocyclic beta-sheet peptide containing two beta-strands from amyloid beta residues 15-23==
<StructureSection load='4q8d' size='340' side='right'caption='[[4q8d]], [[Resolution|resolution]] 1.75&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[4q8d]] is a 2 chain structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4Q8D OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4Q8D 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]] 1.746&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=HAO:{[3-(HYDRAZINOCARBONYL)-4-METHOXYPHENYL]AMINO}(OXO)ACETIC+ACID'>HAO</scene>, <scene name='pdbligand=MPD:(4S)-2-METHYL-2,4-PENTANEDIOL'>MPD</scene>, <scene name='pdbligand=ORN:L-ORNITHINE'>ORN</scene>, <scene name='pdbligand=PHI:IODO-PHENYLALANINE'>PHI</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=4q8d FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4q8d OCA], [https://pdbe.org/4q8d PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4q8d RCSB], [https://www.ebi.ac.uk/pdbsum/4q8d PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4q8d ProSAT]</span></td></tr>
</table>
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
A macrocyclic beta-sheet peptide containing two nonapeptide segments based on Abeta15-23 (QKLVFFAED) forms fibril-like assemblies of oligomers in the solid state. The X-ray crystallographic structure of macrocyclic beta-sheet peptide 3 was determined at 1.75 A resolution. The macrocycle forms hydrogen-bonded dimers, which further assemble along the fibril axis in a fashion resembling a herringbone pattern. The extended beta-sheet comprising the dimers is laminated against a second layer of dimers through hydrophobic interactions to form a fibril-like assembly that runs the length of the crystal lattice. The second layer is offset by one monomer subunit, so that the fibril-like assembly is composed of partially overlapping dimers, rather than discrete tetramers. In aqueous solution, macrocyclic beta-sheet 3, and homologues 4 and 5, form discrete tetramers, rather than extended fibril-like assemblies. The fibril-like assemblies of oligomers formed in the solid state by macrocyclic beta-sheet 3 represent a new mode of supramolecular assembly not previously observed for the amyloidogenic central region of Abeta. The structures observed at atomic resolution for this peptide model system may offer insights into the structures of oligomers and oligomer assemblies formed by full-length Abeta and may provide a window into the propagation and replication of amyloid oligomers.

A Fibril-like Assembly of Oligomers of a Peptide Derived from beta-Amyloid.,Pham JD, Spencer RK, Chen KH, Nowick JS J Am Chem Soc. 2014 Jul 28. PMID:25068693<ref>PMID:25068693</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 4q8d" style="background-color:#fffaf0;"></div>
== References ==
<references/>
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</StructureSection>
[[Category: Large Structures]]
[[Category: Chen KH]]
[[Category: Nowick JS]]
[[Category: Pham JD]]
[[Category: Spencer RK]]