1WDG:
reference: Structural basis for coronavirus-mediated membrane fusion. Crystal structure of mouse hepatitis virus spike protein fusion core., Xu Y, Liu Y, Lou Z, Qin L, Li X, Bai Z, Pang H, Tien P, Gao GF, Rao Z, J Biol Chem 2004 Jul 16;279(29):30514-22. Epub 2004 Apr 27. PMID: 15123674

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