The COVID-19 pandemic caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is a serious public health threat. Most vaccines being developed against SARS-CoV-2 target the highly glycosylated spike protein (S). A good knowledge of the glycosylation profile of this protein is key for successful vaccine development. Unlike the 22 confirmed N-glycosylation sites (NGSs) on the SARS-CoV-2 S, only a few O-glycosylation sites (OGSs) on this protein have been reported. This difference is mainly ascribed to an extremely low O-glycosylation stoichiometry. Herein, we comprehensively analyzed the O-glycosylation profile of recombinant SARS-CoV-2 S employing biomimetic polymer consisting of Trp-Arg monomer. Twenty-six OGSs and 33 O-linked glycans (OLGs) in the SARS-CoV-2 S were unambiguously identified, among which 24 OGSs and 25 OLGs are novel to the SARS-CoV-2 S. Our study reveals the comprehensive O-glycosylation profile of the SARS-CoV-2 S, which might shed light on viral pathobiology and assist in vaccine development.
Comprehensive O-glycosylation analysis of the SARS-CoV-2 spike protein