Article Unexpected Receptor Functional Mimicry Elucidates Activation of Coronavirus Fusion Graphical Abstract Highlights d MERS-CoV/SARS-CoV S composite glycan shields analyzed by cryo-EM and mass spectrometry d Structures of MERS-CoV/SARS-CoV S with neutralizing antibodies from survivors d LCA60 inhibits receptor binding by interacting with MERS- CoV S protein/glycans d S230 blocks receptor binding and triggers fusogenic rearrangements via functional mimicry Authors Alexandra C. Walls, Xiaoli Xiong, Young-Jun Park, ..., Fe´ lix A. Rey, Davide Corti, David Veesler Correspondence