RESEARCH ARTICLE Cryo-EM structure of the SARS coronavirus spike glycoprotein in complex with its host cell receptor ACE2 Wenfei Song1☯, Miao Gui2☯, Xinquan Wang1,3*, Ye Xiang2* 1 The Ministry of Education Key Laboratory of Protein Science, Beijing Advanced Innovation Center for Structural Biology, Collaborative Innovation Center for Biotherapy, School of Life Sciences, Tsinghua University, Beijing, China, 2 Center for Infectious Disease Research, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Beijing Advanced Innovation Center for Structural Biology, Department of Basic Medical Sciences, School of Medicine, Tsinghua University, Beijing, China, 3 Collaborative Innovation Center for Biotherapy, State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, West China Medical School, Sichuan University, Chengdu, Sichuan, China ☯ These authors contributed equally to this work. *