Computational Repurposing of FDA Approved Drugs Against Monkeypox Virus Cysteine Proteinase: A Molecular Docking and Dynamics Simulation Study.

Abstract

Monkeypox is a zoonotic disease caused by a DNA virus known as Monkeypox virus. Generally, Monkeypox disease is considered a self-limiting condition with symptoms similar to that of smallpox disease. Most cases of Monkeypox are considered mild but some patients may suffer from serious complications. Due to the high similarity between Monkeypox virus and smallpox virus, therefore vaccines and antiviral therapies originally intended for use against smallpox can be effective also in Monkeypox infection cases. However, the level of cross-immunity against poxviruses had declined globally because of cessation of vaccination campaigns against smallpox decades ago. As a result, the recent outbreaks in 2022 of Monkeypox in multiple regions of the word have caused public health fears of a new pandemic potential. It is well-known that Monkeypox virus like other poxviruses replicates in the cytoplasm of infected cells by using a number of viral encoded proteins like cysteine proteinase. Generally, proteases enzymes play a critical role in viral replication cycle through catalysis of precursor polyproteins cleavage. Therefore, proteases enzymes like cysteine proteinase represent an attractive target to design novel antiviral drugs. Unfortunately, the cysteine proteinase enzyme of Monkeypox virus is still not yet crystallized and this can negatively impact efforts for structure-based drug design and screening. As such, we have chosen to computationally model the secondary and tertiary structures of Monkeypox cysteine proteinase by using the primary amino acids sequence of the enzyme. And after refinement and validation of the modelled protein, we have screened a library of 1,615 FDA approved drug molecules against Monkeypox cysteine proteinase by using AutoDock Vina. Then, the best hits were further assessed by molecular dynamics simulation for 20 nanoseconds. The aim of this in-silico study is to repurpose approved drugs as a potential inhibitor against Monkeypox cysteine proteinase. The findings of this in-silico study refer to the potential ability of the antibiotic Tetracycline to inhibit the cysteine proteinase of Monkeypox virus. However, the lack of crystallization data regarding this proteinase enzyme makes these findings not conclusive.

Update on monkeypox virus infection: Focusing current treatment and prevention approaches

“…It was found that dihydroergotamine showed efficient binding with the proteins and inhibited Mpox cysteine proteinase. These findings support further in-vitro and in-vivo studies on dehydroergotamine for potential therapy against Mpox [60].…”

A multi-targeted computational drug discovery approach for repurposing tetracyclines against monkeypox virus

“…Molecular dynamics simulation mainly focuses on calculating the natural dynamics of biomolecular structures on the different timescale in a solution. This also helps calculate each atom's fluid properties and movement in a system in a given set of times 43 . So, the selected protein–ligand complexes of both MPXV proteins were observed to understand the stability of the complex under 300 ns MD simulation.…”

Exploring the natural products chemical space to abrogate the F3L-dsRNA interface of monkeypox virus to enhance the immune responses using molecular screening and free energy calculations

“…A similar approach has been used by the previous study which uses the FDA approved drugs against the three different targets such as topoisomerase1, p37, and thymidylate kinase of the monkey pox virus (Srivastava et al, 2023). Another study used drug screening against monkey pox virus cysteine proteinase (Odhar, 2022). The drugs IDs, 2D structures, name and docking score are shown in Table 1.…”