Amyloid-like Behavior in Abiotic, Amphiphilic Foldamers
详细信息 查看全文
- 作者：Valerie J. Bradford ; Brent L. Iverson
- 刊名：Journal of the American Chemical Society
- 出版年：2008
- 出版时间：January 30, 2008
- 年：2008
- 卷：130
- 期：4
- 页码：1517 - 1524
- 全文大小：365K
- 年卷期：v.130,no.4(January 30, 2008)
- ISSN：1520-5126
文摘
Previously, we reported an abiotic amphiphilic foldamer that, upon heating, undergoes anirreversible conformational change to a highly aggregated state (Nguyen, J.Q.; Iverson, B.L. J. Am. Chem.Soc. 1999, 121, 2639-2640.). Herein, we extend this work through the study of a series of structurallyrelated amphiphilic foldamers and present a more refined model of their conformational switching behavior.Prior to heating, all foldamers of the series exhibited spectral characteristics consistent with folding in thepleated, stacked geometry characteristic of this class of foldamer. Following heating at 80 
C, three of thefour molecules exhibited irreversible aggregation to produce hydrogels. The hydrogels were characterizedby rheology measurements, and circular dichroism spectra revealed that hydrogel formation was dependenton highly ordered intermolecular assembly, conceptually analogous to protein amyloid formation. Hydrogelformation had the effect of amplifying the subtle structural differences between molecules, as the threeamphiphilic foldamer constitutional isomers that formed hydrogels upon heating displayed significantdifferences in hydrogel properties. Taking a global view, our results indicate that amyloid-like behavior isnot unique to proteins but may be a relatively general property of amphiphilic folding molecules in aqueoussolution.
C, three of thefour molecules exhibited irreversible aggregation to produce hydrogels. The hydrogels were characterizedby rheology measurements, and circular dichroism spectra revealed that hydrogel formation was dependenton highly ordered intermolecular assembly, conceptually analogous to protein amyloid formation. Hydrogelformation had the effect of amplifying the subtle structural differences between molecules, as the threeamphiphilic foldamer constitutional isomers that formed hydrogels upon heating displayed significantdifferences in hydrogel properties. Taking a global view, our results indicate that amyloid-like behavior isnot unique to proteins but may be a relatively general property of amphiphilic folding molecules in aqueoussolution.