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bioRxiv · 10.1101/2020.07.12.199588

Cold sensitivity of the SARS-CoV-2 spike ectodomain

Edwards, R. J.·Mansouri, K.·Stalls, V.·Manne, K.·Watts, B.·Parks, R.·Gobeil, S. M. C.·Janowska, K.·Li, D.·Lu, X.·Deyton, M.·Sprenz, J.·Williams, W.·Saunders, K.·Sempowski, G. D.·Henderson, R.·Alam, M.·Haynes, B. F.·Acharya, P.
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Abstract

The SARS-CoV-2 spike (S) protein, a primary target for COVID-19 vaccine development, presents its Receptor Binding Domain in two conformations: receptor-accessible "up" or receptor-inaccessible "down" conformations. Here, we report that the commonly used stabilized S ectodomain construct "2P" is sensitive to cold temperature, and that this cold sensitivity is resolved in a "down" state stabilized spike. Our results will impact structural, functional and vaccine studies that use the SARS-CoV-2 S ectodomain.

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Edwards, R. J., Mansouri, K., Stalls, V., Manne, K., Watts, B., Parks, R., Gobeil, S. M. C., Janowska, K., Li, D., Lu, X., Deyton, M., Sprenz, J., Williams, W., Saunders, K., Sempowski, G. D., Henderson, R., Alam, M., Haynes, B. F., Acharya, P.. 2020-07-13. Cold sensitivity of the SARS-CoV-2 spike ectodomain. https://doi.org/10.1101/2020.07.12.199588

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