Author(s)

Yuri Alves de Oliveira Só^1*, Marcelo Lopes Pereira Junior², Wiliam Ferreira Giozza², Rafael Timóteo de Sousa Junior², Ricardo Gargano¹, Luiz Antônio Ribeiro Júnior¹

¹Institute of Physics, University of Brasília, Brasília, Brazil.
²Department of Electrical Engineering, University of Brasília, Brasília, Brazil.

Virtual screening can be a helpful approach to propose treatments for COVID-19 by developing inhibitors for blocking the attachment of the virus to human cells. This study uses molecular docking, recovery time and dynamics to analyze if potential inhibitors of main protease (M^pro) of SARS-CoV-2 can interfere in the attachment of nanobodies, specifically Nb20, in the receptor binding domain (RBD) of SARS-CoV-2. The potential inhibitors are four compounds previously identified in a fluorescence resonance energy transfer (FRET)-based enzymatic assay for the SARS-CoV-2 M^pro: Boceprevir, Calpain Inhibitor II, Calpain Inhibitor XII, and GC376. The findings reveal that Boceprevir has the higher affinity with the RBD/Nb20 complex, followed by Calpain Inhibitor XII, GC376 and Calpain Inhibitor II. The recovery time indicates that the RBD/Nb20 complex needs a relatively short time to return to what it was before the presence of the ligands. For the RMSD the Boceprevir and Calpain Inhibitor II have the shortest interaction times, while Calpain Inhibitor XII shows slightly more interaction, but with significant pose fluctuations. On the other hand, GC376 remains stably bound for a longer duration compared to the other compounds, suggesting that they can potentially interfere with the neutralization process of Nb20.

SARS-CoV-2, Main protease M^pro, Boceprevir, Calpain Inhibitor II, Calpain Inhibitor XII, GC376, Nanobody Nb20, In Silico

de Oliveira Só, Y. , Junior, M. , Giozza, W. , de Sousa Junior, R. , Gargano, R. and Júnior, L. (2023) In Silico Evaluation of the Potential Interference of Boceprevir, Calpain Inhibitor II, Calpain Inhibitor XII, and GC376 in the Binding of SARS-CoV-2 Spike Protein to Human Nanobody Nb20. Open Journal of Biophysics, 13, 35-49. doi: 10.4236/ojbiphy.2023.133004.