6ZP2:
reference: A thermostable, closed SARS-CoV-2 spike protein trimer., Xiong X, Qu K, Ciazynska KA, Hosmillo M, Carter AP, Ebrahimi S, Ke Z, Scheres SHW, Bergamaschi L, Grice GL, Zhang Y, Nathan JA, Baker S, James LC, Baxendale HE, Goodfellow I, Doffinger R, Briggs JAG, Nat Struct Mol Biol. 2020 Jul 31. pii: 10.1038/s41594-020-0478-5. doi:, 10.1038/s41594-020-0478-5. PMID: 32737467

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