Mechanical stress affects glucagon fibrillation kinetics and fibril structure

© 2011 American Chemical Society

Bibliographische Detailangaben
Veröffentlicht in:Langmuir : the ACS journal of surfaces and colloids. - 1999. - 27(2011), 20 vom: 18. Okt., Seite 12539-49
1. Verfasser: Macchi, Francesca (VerfasserIn)
Weitere Verfasser: Hoffmann, Søren V, Carlsen, Martin, Vad, Brian, Imparato, Alberto, Rischel, Christian, Otzen, Daniel E
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2011
Zugriff auf das übergeordnete Werk:Langmuir : the ACS journal of surfaces and colloids
Schlagworte:Journal Article Research Support, Non-U.S. Gov't Multiprotein Complexes Glucagon 9007-92-5
Beschreibung
Zusammenfassung:© 2011 American Chemical Society
Mechanical stress can strongly influence the capability of a protein to aggregate and the kinetics of aggregation, but there is little insight into the underlying mechanism. Here we study the effect of different mechanical stress conditions on the fibrillation of the peptide hormone glucagon, which forms different fibrils depending on temperature, pH, ionic strength, and concentration. A combination of spectroscopic and microscopic data shows that fibrillar polymorphism can also be induced by mechanical stress. We observed two classes of fibrils: a low-stress and a high-stress class, which differ in their kinetic profiles, secondary structure as well as morphology and that are able to self-propagate in a template-dependent fashion. The bending rigidity of the low-stress fibrils is sensitive to the degree of mechanical perturbation. We propose a fibrillation model, where interfaces play a fundamental role in the switch between the two fibrillar classes. Our work also raises the cautionary note that mechanical perturbation is a potential source of variability in the study of fibrillation mechanisms and fibril structures
Beschreibung:Date Completed 14.02.2012
Date Revised 11.10.2011
published: Print-Electronic
Citation Status MEDLINE
ISSN:1520-5827
DOI:10.1021/la202125c