6B3O:
reference: Tectonic conformational changes of a coronavirus spike glycoprotein promote membrane fusion., Walls AC, Tortorici MA, Snijder J, Xiong X, Bosch BJ, Rey FA, Veesler D, Proc Natl Acad Sci U S A. 2017 Oct 17;114(42):11157-11162. doi:, 10.1073/pnas.1708727114. Epub 2017 Oct 3. PMID: 29073020

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