Nanomechanics and intermolecular forces of amyloid revealed by four-dimensional electron microscopy
Abstract
The biomechanics of amyloid underlies its function in living organisms. We use four-dimensional electron microscopy to systematically dissect the nanoscale origins of amyloid elasticity by measuring the bond stiffnesses of the intermolecular forces stabilizing each of its three characteristic packing interfaces. We find amyloid to have a pronounced mechanical anisotropy with longitudinal, hydrogen bonding 20 times stiffer than transverse, amphiphilic, and electrostatic interactions. Such strongly anisotropic elastic properties are likely to give rise to length-dependent mechanical behavior with short fibrils possessing significantly different material properties than longer fibrils. This is of great importance in understanding fibril–membrane interactions and fragmentation mechanisms, both of which are thought to play a crucial role in the spread of amyloid diseases.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Mar 02, 2015
- Source ID
- 10.1073/pnas.1502214112
Entities
People
- Ahmed Zewail
- Anthony W. P. Fitzpatrick
- Giovanni M. Vanacore
Organizations
- Air Force Office of Scientific Research
- California Institute of Technology
- National Science Foundation