Mutations, Recombination and Insertion in the Evolution of 2019-nCoV

Aiping Wu; Peihua Niu; Lulan Wang; Hangyu Zhou; Xiang Zhao; Wenling Wang; Jingfeng Wang; Chengyang Ji; Xiao Ding; Xianyue Wang; Roujian Lu; Sarah Gold; Saba Aliyari; Shilei Zhang; Ellee Vikram; Angela Zou; Emily Lenh; Janet Chen; Fei Ye; Na Han; Yousong Peng; Haitao Guo; Guizhen Wu; Taijiao Jiang; Wenjie Tan; Genhong Cheng

The copyright holder for this preprint (which was not peer-reviewed) is the . https://doi.org/10.1101/2020.02.29.971101 doi: bioRxiv preprint that the RBM of the clade II viruses has regions with 5 and 13-14 amino acids shorter than that of the clade I viruses (Fig. 4B) . Previous structural analysis have demonstrated that the 13-14 amino acid region of the SARS RBM forms a distinct loop structure, which is stabilized with a disulfide bond between two cysteine residues 9,15,16,21 . Although the amino acid sequences of 2019-nCoV within this loop region are very different from those 5 of human SARS, the two cysteine residues are conserved (Fig. 4B) . Interestingly, all the CoV viruses known to use ACE2 as entry receptor are within the clade I, including the 2019-nCoV, which can also infect cells through ACE2 receptor-based on recent studies 22 (Fig. S5 ). On the other hand, there is no report on using ACE2 as entry receptor for the clade II viruses, despite their overall genome sequence homology with 2019-nCoV.