Sulphated polysaccharides from seaweeds as potential entry inhibitors and vaccine adjuvants against SARS-CoV-2 RBD spike protein: a computational approach

Abstract

The health pandemic (covid-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has infected, to date, over 233 million people and over 4.77 million deaths worldwide. Therefore, it is important to offer a wide understanding of the ability of potential antiviral biomolecules to combat this virus, which begins to develop new variants, potentially more transmissible and infectious. Sulphated polysaccharides (SPs) from seaweeds have been reported for their antiviral activity and their potential as vaccine adjuvants. However, their effect against SARS-CoV-2 remains very limited. In this study, seventeen ligands of SPs were screened for effective interaction with the domain (RBD) spike protein using a computational approach. The obtained results indicated that two PS ligands (Xylan sulphate and Heparin tetrasaccharide N-sulphated) effectively bind to the RBD protein and could efficiently inhibit viral entry. Overall, data support the potential importance of SPs against SARS-CoV-2 as entry inhibitors and vaccine adjuvants. Highlights Seventeen ligands of sulphated polysaccharides (SPs) were subjected to a molecular docking to assess their interaction with SARS-CoV-2 RBD spike protein; Two SP ligands showed an effective binding affinity to the RBD protein and could efficiently inhibit viral entry; One effective SP ligand (Xylan Sulphate) was predicted using ADMETox evaluation as good inhibitor; Effective candidates can have an importance against SARS-CoV-2 as entry inhibitors and vaccine adjuvants.

Keywords

• covid-19
• sars-cov-2 rbd
• sulphated polysaccharides
• molecular docking entry inhibitors
• vaccine adjuvants