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Interactions with and Membrane Permeabilization of Brain Mitochondria by Amyloid Fibrils
Published on: September 28, 2019
Amyloid protofibril is highly voluminous and compressible
Kazuyuki Akasaka1, Abdul Raziq Abdul Latif, Akihiro Nakamura
1Department of Biotechnological Science, School of Biology-Oriented Science and Technology, Kinki University, 930 Nishimitani, Kinokawa, Wakayama 649-6493, Japan. akasaka@waka.kindai.ac.jp
Biochemistry
|August 25, 2007
Summary
Amyloid protofibrils are highly voluminous and compressible, with distinct changes in protein volume and compressibility observed during their formation. These findings reveal the dynamic, cavity-rich nature of amyloid structures.
Area of Science:
- Biophysics
- Protein Chemistry
- Structural Biology
Background:
- Amyloid protofibrils are associated with various diseases.
- Understanding their structural properties is crucial for therapeutic development.
- Previous studies lacked direct measurements of volume and compressibility changes during protofibril formation.
Purpose of the Study:
- To directly measure partial specific volume and compressibility changes during amyloid protofibril formation.
- To characterize the physical properties of amyloid protofibrils.
- To elucidate the structural dynamics of protein aggregation.
Main Methods:
- Utilized a high-precision density meter to measure partial specific volume.
- Employed an ultrasonic velocity meter to determine adiabatic compressibility.
- Monitored time-dependent changes in intrinsically disordered hen lysozyme.
Main Results:
- Observed a significant increase in partial specific volume from 0.684 to 0.724 mL/g.
- Detected a substantial change in adiabatic compressibility from negative to positive values.
- Identified two distinct phases in volume and compressibility changes, with one preceding beta-structure development.
Conclusions:
- Amyloid protofibrils are highly voluminous and compressible entities.
- These properties suggest a cavity-rich and fluctuating structure.
- The observed changes indicate complex structural rearrangements during fibril formation.
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