Abstract
We provide a constitutive model of semiflexible and rigid amyloid fibril networks by combining the affine thermal model of network elasticity with the Derjaguin-Landau-Vervey-Overbeek (DLVO) theory of electrostatically charged colloids. When compared to rheological experiments on -lactoglobulin and lysozyme amyloid networks, this approach provides the correct scaling of elasticity versus both concentration ( and for semiflexible and rigid fibrils, respectively) and ionic strength ( and for -lactoglobulin and lysozyme, independent from fibril flexibility). The pivotal role played by the screening salt is to reduce the electrostatic barrier among amyloid fibrils, converting labile physical entanglements into long-lived cross-links. This gives a power-law behavior of with having exponents significantly larger than in other semiflexible polymer networks (e.g., actin) and carrying DLVO traits specific to the individual amyloid fibrils.
- Received 5 October 2017
- Revised 2 February 2018
DOI:https://doi.org/10.1103/PhysRevLett.120.158103
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