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bioRxiv · 10.1101/2020.03.28.013276

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

Zhang, Y.·Zhao, W.·Mao, Y.·Wang, S.·Zhong, Y.·Su, T.·Gong, M.·Lu, X.·Cheng, J.·Yang, H.
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Abstract

SummaryThe glycoprotein spike (S) on the surface of SARS-CoV-2 is a determinant for viral invasion and host immune response. Herein, we characterized the site-specific N-glycosylation of S protein at the level of intact glycopeptides. All 22 potential N-glycosites were identified in the S-protein protomer and were found to be preserved among the 753 SARS-CoV-2 genome sequences. The glycosites exhibited glycoform heterogeneity as expected for a human cell-expressed protein subunits. We identified masses that correspond to 157 N-glycans, primarily of the complex type. In contrast, the insect cell-expressed S protein contained 38 N-glycans, primarily of the high-mannose type. Our results revealed that the glycan types were highly determined by the differential processing of N-glycans among human and insect cells. This N-glycosylation landscape and the differential N-glycan patterns among distinct host cells are expected to shed light on the infection mechanism and present a positive view for the development of vaccines and targeted drugs.Competing Interest StatementThe authors have declared no competing interest.AbbreviationsACE2angiotensin-converting enzyme IICryo-EMcryoelectron microscopyEenvelope proteinHCoV-NL63human coronavirus NL63Mmembrane proteinMSmass spectrometryMERS-CoVMiddle East respiratory syndrome coronavirusNnucleocapsid proteinRBDreceptor-binding domainSspike proteinSARS-CoV-2severe acute respiratory syndrome coronavirusSCEstepped collision energyZic-HILICzwitterionic hydrophilic interaction liquid chromatographyView Full Text

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Zhang, Y., Zhao, W., Mao, Y., Wang, S., Zhong, Y., Su, T., Gong, M., Lu, X., Cheng, J., Yang, H.. 2020-03-29. Site-specific N-glycosylation Characterization of Recombinant SARS-CoV-2 Spike Proteins using High-Resolution Mass Spectrometry. https://doi.org/10.1101/2020.03.28.013276

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