# Glycans Modulate the Adsorption of RBD Glycoproteins on Polarizable Surfaces

## TL;DR

This study explores how glycans affect how RBD glycoproteins from SARS-CoV-2 stick to different surfaces, revealing new insights into virus-surface interactions.

## Contribution

The study reveals novel glycan-mediated adsorption phenomena and their role in modulating RBD conformational dynamics on polarizable surfaces.

## Key findings

- Hydrophobic surfaces support stable adsorption of both open and closed RBD conformations.
- Glycans modulate closed-RBD adsorption, either enhancing or impeding it depending on conformation and mutations.
- Findings align with scaled-up simulations of the complete spike ectodomain glycoprotein.

## Abstract

Numerous respiratory viruses are transmitted via airborne
microdroplets
that frequently adhere to fomites. Understanding the behavior of these
phenomenologically rich bio-material interfaces remains an open issue.
Here, we tackle the complex interplay between glycans and protein
conformational dynamics during adsorption onto polarizable surfaces,
focusing on the potential of glycans as molecular interaction modulators.
We employ molecular dynamics simulations to dissect the interactions
of the Receptor Binding Domain (RBD) glycoproteins from different
SARS-CoV-2 variants of concern (VoC), in both open and closed conformations,
with polarizable planar interfaces. Advanced analysis using 2D space
reveals distinct adsorption mechanisms depending on the initial loci
of the glycan within the protein wall. Hydrophobic surfaces facilitate
stable adsorption for both RBD conformations. Conversely, hydrophilic
surfaces exhibit reduced adsorption, particularly for the closed-RBD,
where glycans predominantly form hydrogen bonds. Glycans significantly
modulate closed-RBD adsorption, either enhancing it by permanent tethering
or impeding it depending on the initial conformation and protein mutations
(Omicron). Results for the individual RBDs are consistent with scaled-up
simulations for the complete spike ectodomain glycoprotein. Our findings
unveil novel glycan-mediated adsorption phenomena and provide fundamental
insights into glycoprotein–surface interactions, paving the
way for understanding glycan roles in glycoprotein–fomite adsorption,
protein aggregation, and recognition at polarizable biological interfaces.