Recombinant SARS-CoV-2 S Protein Binds to Glycans of the Lactosamine Family in vitro

Many viruses, beside binding to their main cell target, interact with other molecules that promote virus adhesion to the cell; often, these additional targets are glycans. The main receptor for SARS-CoV-2 is a peptide motif in the ACE2 protein. We studied interaction of the recombinant SARS-CoV-2 spike (S) protein with an array of glycoconjugates, including various sialylated, sulfated, and other glycans, and found that the S protein binds some (but not all) glycans of the lactosamine family. We suggest that parallel influenza infection will promote SARS-CoV-2 adhesion to the respiratory epithelial cells due to the unmasking of lactosamine chains by the influenza virus neuraminidase. Electronic supplementary material Supplementary material is available in the online version of this article at 10.1134/S0006297921030019 and on the journal website (http://protein.bio.msu.ru/biokhimiya).