Protein-Dominated Adsorption and Protection on Viruses in Model EPS Components: Insight from Multiscale Mechanistic Analysis

However, the molecular mechanisms underlying EPS–virus interactions and their environmental implications remain unclear. This study employed three representative model EPS components, i.e., proteins, polysaccharides, and humic substances, and systematically investigated EPS–virus interaction mechanisms with T7 bacteriophage as a virus surrogate.

By integrating surface plasmon resonance analysis, double-layer agar plaque assays and qPCR, we demonstrated that proteins dominate virus adsorption and stability within simulated EPS matrices. With rapid protein–virus association (<i>k</i>_a up to 10⁶ M^–1·s^–1) and moderate binding affinities (<i>K</i>_D in the 10^–6–10^–7 M range), roughly 60% of viral infectivity was preserved over 8 days, in contrast to the 4.58% observed in the control.