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A Tailored HPLC Purification Protocol That Yields High-purity Amyloid Beta 42 and Amyloid Beta 40 Peptides, Capable of Oligomer Formation
Published on: March 27, 2017
Hydration profiles of amyloidogenic molecular structures
Florin Despa1, Ariel Fernández, L Ridgway Scott
1Department of Pharmacology, University of California, Davis, CA 95616, USA. fdespa@ucdavis.edu
Journal of Biological Physics
|August 12, 2009
Summary
Protein aggregation, a cause of toxic cellular deposits, can be detected early using magnetic resonance (MR) imaging. Different water compartments within protein aggregates create distinct MR signals, differentiating normal proteins from toxic ones.
Area of Science:
- Biophysics
- Biochemistry
- Medical Imaging
Background:
- Protein hydration shells contain structured and bulk-like water.
- Increased bulk-like water patches correlate with protein aggregation.
- Protein aggregates are toxic and require early detection.
Purpose of the Study:
- Differentiate normal proteins from aggregated isomers using water compartmentalization and MR signals.
- Develop mathematical models to predict MR responses based on water and protein assembly characteristics.
- Explain MR contrast patterns in amyloid diseases.
Main Methods:
- Analyzing the partition of bulk, caged, and surface hydration water.
- Deriving mathematical equations relating water compartmentalization to hydration fraction and packing density.
- Predicting MR signal shifts based on protein aggregation states.
Main Results:
- Single units and compact aggregates (no interstitial water) shift MR signals to hyperintensity (bright spots), indicating bulk water.
- Large plaques (caging significant water) generate hypointensity (dark spots), typical of correlated water.
- Amyloids can exhibit both dark and bright spots on MR images.
Conclusions:
- MR imaging can distinguish normal proteins from toxic aggregates based on water signal characteristics.
- Bright spots on MR images may indicate early-stage amyloid development.
- Findings offer a new approach for identifying protein aggregation diseases like amyloidosis.
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