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bioRxiv · 10.1101/2021.04.09.439181

Theoretical causes of the Brazilian P.1 and P.2 lineages of the SARS-CoV-2 virus through molecular dynamics

Lima de Oliveira, M. D.·Teixeira de Oliveira, K. M.·Nunes da Silva, J.·Santos, C.·Bessa, J.·de Freitas Rodrigues, R.
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Abstract

The new {beta}-coronavirus has been causing sad losses around the world and the emergence of new variants has caused great concern. This pandemic is of a proportion not seen since the Spanish Flu in 1918. Thus, throughout this research, the B.1.1.28 lineage of the P.1 clade (K417T, N501Y, E484K) that emerged in Brazil was studied, as well as the latest Delta variant. This is because the molecular mechanisms by which phenotypic changes in transmissibility or mortality remain unknown. Through molecular dynamics simulations with the NAMD 3 algorithm in the 50ns interval, it was possible to understand the impact on structural stabilization on the interaction of the ACE2-RBD complex, as well as simulations in 30ns for the neutralizing antibody P2B-2F6, with this antibody was derived from immune cells from patients infected with SARS-CoV-2. Although not all molecular dynamics analyzes support the hypothesis of greater stability in the face of mutations, there was a predominance of low fluctuations. Thus, 3 (three) analyzes corroborate the hypothesis of greater ACE2-RBD stability as a result of P.1, among them: Low mean RMSF values, greater formation of hydrogen bonds and low solvent exposure measured by the SASA value. An inverse behavior occurs in the interaction with neutralizing antibodies, since the mutations induce greater instability and thus hinder the recognition of antibodies in neutralizing the Spike protein, where we noticed a smaller number of hydrogen bonds as a result of P.1. Through MM-PBSA energy decomposition, we found that Van der Waals interactions predominated and were more favorable when the structure has P.1 strain mutations. Therefore, we believe that greater stabilization of the ACE2-RBD complex may be a plausible explanation for why some mutations are converging in different strains, such as E484K and N501Y. The P.1 concern variant still makes the Spike protein recognizable by antibodies, and therefore, even if the vaccines efficacy can be diminished, there are no results in the literature that nullify them.

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Lima de Oliveira, M. D., Teixeira de Oliveira, K. M., Nunes da Silva, J., Santos, C., Bessa, J., de Freitas Rodrigues, R.. 2021-04-10. Theoretical causes of the Brazilian P.1 and P.2 lineages of the SARS-CoV-2 virus through molecular dynamics. https://doi.org/10.1101/2021.04.09.439181

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