Site-specific N-glycosylation Characterization of Recombinant SARS-CoV-2 Spike Proteins using High-Resolution Mass Spectrometry

Yong Zhang; Wanjun Zhao; Yonghong Mao; Shisheng Wang; Yi Zhong; Tao Su; Meng Gong; Xiaofeng Lu; Jingqiu Cheng; Hao Yang

Following further comparison with the closely related SARS-CoV S protein (5, 21) , 18 of the 22 N-glycosites were identified as conserved in the SARS-CoV-2 S protein, indicating the importance of glycosylation of the virus. Four newly arisen N-glycosites (N17, N74, N149, and N657) are located in the SARS-CoV-2 S protein S1 subunit away from the RBD. Moreover, four previously confirmed N-glycosites (N29, N73, N109, and N357) in the SARS-CoV S protein were missing in SARS-CoV-2 S, one of which (N357) lies in the RBD (Fig. S6 ). Additionally, two N-glycosites (N1158 and N1173) identified in SARS-CoV-2 S in this study were not detected in SARS-CoV S (N1140 and N1155) in previous studies (5, 21) . Our results suggest that the preferential change of the glycosylation landscape of the S1 subunit . CC-BY-NC-ND 4.0 International license author/funder. It is made available under a The copyright holder for this preprint (which was not peer-reviewed) is the . https://doi.org/10.1101/2020.03.28.013276 doi: bioRxiv preprint tends to change the distribution of glycan shield, especially in the N terminal half of S1 (Fig. S6 ).