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bioRxiv · 10.1101/2022.01.27.478066

Interconversion between Serum Amyloid A native and fibril conformations

Yasar, F.·Sheridan, M. S.·Hansmann, U. H. E.
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Abstract

Overexpression of Serum Amyloid A (SAA) can lead to a form of amyloidosis where the fibrils are made of SAA fragments, most often SAA1-76. Using Replica-Exchange-with-Tunneling, we study the conversion of a SAA1-76 chain between a the folded conformation and a fibril conformation. We find that the basins in the free energy landscape corresponding to the two motifs are separated by barriers of only about 2-3 kBT. Crucial for the assembly into the fibril structure is the salt bridge 26E-34K that provides a scaffold for forming the fibril conformation.

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Yasar, F., Sheridan, M. S., Hansmann, U. H. E.. 2022-01-28. Interconversion between Serum Amyloid A native and fibril conformations. https://doi.org/10.1101/2022.01.27.478066

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