View source for 9bi3


==Crystal structure of macrocycle containing Abeta17-23 (LVF(a-Me-F)AED) and Abeta30-36 (AIIGL(ORN)V)==
<StructureSection load='9bi3' size='340' side='right'caption='[[9bi3]], [[Resolution|resolution]] 1.00&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[9bi3]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=9BI3 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=9BI3 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&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=A1APM:(2~{S})-2-azanyl-2-methyl-3-phenyl-propanoic+acid'>A1APM</scene>, <scene name='pdbligand=ORN:L-ORNITHINE'>ORN</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=9bi3 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=9bi3 OCA], [https://pdbe.org/9bi3 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=9bi3 RCSB], [https://www.ebi.ac.uk/pdbsum/9bi3 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=9bi3 ProSAT]</span></td></tr>
</table>
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
The assembly of the beta-amyloid peptide Abeta into toxic oligomers plays a significant role in the neurodegeneration associated with the pathogenesis of Alzheimer's disease. Our laboratory has developed N-methylation as a tool to enable X-ray crystallographic studies of oligomers formed by macrocyclic beta-hairpin peptides derived from Abeta. In this investigation, we set out to determine whether alpha-methylation could be used as an alternative to N-methylation in studying the oligomerization of a beta-hairpin peptide derived from Abeta. alpha-Methylation permits the crystallographic assembly of a triangular trimer and ball-shaped dodecamer, resembling assemblies formed by the N-methylated homolog. Subtle differences are observed in the conformation of the alpha-methylated peptide when compared to the N-methylated homolog. Notably, alpha-methylation appears to promote a flatter and more extended beta-sheet conformation than that of N-methylated beta-sheets or a typical unmodified beta-sheet. alpha-Methylation provides an alternative to N-methylation in X-ray crystallographic studies of oligomers formed by peptides derived from Abeta, with the attractive feature of preserving NH hydrogen-bond donors along the peptide backbone.

alpha-Methylation Enables the X-ray Crystallographic Observation of Oligomeric Assemblies Formed by a beta-Hairpin Peptide Derived from Abeta.,Samdin TD, Kreutzer AG, Sahrai V, Wierzbicki M, Nowick JS J Org Chem. 2025 Jan 10;90(1):394-400. doi: 10.1021/acs.joc.4c02344. Epub 2024 , Dec 17. PMID:39689228<ref>PMID:39689228</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 9bi3" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Homo sapiens]]
[[Category: Large Structures]]
[[Category: Kreutzer AG]]
[[Category: Nowick JS]]
[[Category: Samdin TD]]
[[Category: Wierzbicki M]]