Gramicidin S and Melittin - Potential anti-viral therapeutic peptides to treat SARS-CoV-2 infection

Abstract

The COVID19 pandemic has resulted in multipronged approaches for treatment of the disease. Since de novo discovery of drugs is time consuming, repurposing of molecules is now considered as one of the alternative strategies to treat COVID19. Antibacterial peptides are being recognized as attractive candidates for repurposing to treat viral infections. In this study, we describe the anti-SARS-CoV-2 activity of gramicidin S and melittin peptides obtained from Bacillus brevis and bee venom respectively. Our in vitro antiviral assay results showed significant decrease in the viral load compared to the untreated group with no/very less cytotoxicity. The EC50 values for gramicidin S and melittin are calculated as 1.571μg and 0.656μg respectively. Both the peptides treated to the SARS-CoV-2 infected Vero cells showed viral clearance from 12 hours onwards with a maximal clearance after 24 hours post infection. Based on proteome analysis it was found that more than 250 proteins were found to be differentially regulated in the gramicidin S and melittin treated SARS-CoV-2 infected Vero cells against control SARS-CoV-2 infected Vero cells after 24 and 48 hours post infection. The identified proteins were found to be associated in the metabolic and mRNA processing of the Vero cells post-treatment and infection. Both these peptides could be attractive candidates for repurposing to treat SARS-CoV-2 infection.

Therapeutic Potential of Melittin Peptide: Major Pain-Producing Substance of European Honeybee (<em>Apis mellifera</em>) Venom against Several Communicable and Non-Communicable Diseases

“…It acted with an IC50 of 2.4 μg/ml (for HIV-1 NLHX) and 3.6 μg/ml (for HIV-1 NLYU2), and it did not affect the vaginal epithelial cells (Hood et al, 2013). Furthermore, In-vitro bioassays indicate that MEL can decrease the relative viral load of SARS-CoV-2 by half at 0.656 μg for MOI = 0.1 (EC50) (Ghalib et al, 2021).…”