Timeline of changes in spike conformational dynamics in emergent SARS-CoV-2 variants reveal progressive stabilization of trimer stalk with altered NTD dynamics
Abstract
SARS-CoV-2 emergent variants are characterized by increased viral fitness and each shows multiple mutations predominantly localized to the spike (S) protein. Here, amide hydrogen/deuterium exchange mass spectrometry has been applied to track changes in S dynamics from multiple SARS-CoV-2 variants. Our results highlight large differences across variants at two loci with impacts on S dynamics and stability. A significant enhancement in stabilization first occurred with the emergence of D614G S followed by smaller, progressive stabilization in subsequent variants. Stabilization preceded altered dynamics in the N-terminal domain, wherein Omicron BA.1 S showed the largest magnitude increases relative to other preceding variants. Changes in stabilization and dynamics resulting from S mutations detail the evolutionary trajectory of S in emerging variants. These carry major implications for SARS-CoV-2 viral fitness and offer new insights into variant-specific therapeutic development.
Data availability
We have made raw files, ProteinLynx Global Server 3.0 search outputs, and Dynamx files used for HDXMS analysis available through ProteomeXchange. The dataset can be found in the PRIDE repository with identifier PXD040717.
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Funding
No external funding was received for this work.
Reviewing Editor
- Rina Rosenzweig, Weizmann Institute of Science, Israel
Version history
- Received: August 10, 2022
- Preprint posted: August 29, 2022 (view preprint)
- Accepted: February 16, 2023
- Accepted Manuscript published: March 17, 2023 (version 1)
- Version of Record published: March 28, 2023 (version 2)
Copyright
© 2023, Braet et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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