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bioRxiv · 10.1101/2021.05.18.444723

The effect of SARS-COV-2 Infections on Amyloid Formation of Serum Amyloid A

Jana, A. K.·Greenwood, A. B.·Hansmann, U. H. E.
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Abstract

A marker for the severeness and disease progress of COVID-19 is overexpression of serum amyloid A (SAA) to levels that in other diseases are associated with a risk for SAA amyloidosis. In order to understand whether SAA amyloidosis could also be a long-term risk of SARS-COV-2 infections we have used long all-atom molecular dynamic simulations to study the effect of a SARS-COV-2 protein segment on SAA amyloid formation. Sampling over 40 {micro}s we find that presence of the nine-residue segment SK9, located at the C-terminus of the Envelope protein, increases the propensity for SAA fibril formation by three mechanisms: it reduces the stability of the lipid-transporting hexamer shifting the equilibrium toward monomers, it increases the frequency of aggregation-prone configurations in the resulting chains, and it raises the stability of SAA fibrils. Our results therefore suggest that SAA amyloidosis and related pathologies may be a long-term risk of SARS-COV-2 infections.

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Jana, A. K., Greenwood, A. B., Hansmann, U. H. E.. 2021-05-19. The effect of SARS-COV-2 Infections on Amyloid Formation of Serum Amyloid A. https://doi.org/10.1101/2021.05.18.444723

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