Neutralizing Effect of Synthetic Peptides toward SARS-CoV-2

Abstract

The outbreak caused by SARS-CoV-2 has taken many lives worldwide. Although vaccination has started, the development of drugs to either alleviate or abolish symptoms of COVID-19 is still necessary. Here, four synthetic peptides were assayed regarding their ability to protect Vero E6 cells from SARS-CoV-2 infection and their toxicity to human cells and zebrafish embryos. All peptides had some ability to protect cells from infection by SARS-CoV-2 with the D614G mutation. Molecular docking predicted the ability of all peptides to interact with and induce conformational alterations in the spike protein containing the D614G mutation. PepKAA was the most effective peptide, by having the highest docking score regarding the spike protein and reducing the SARS-CoV-2 plaque number by 50% (EC50) at a concentration of 0.15 mg mL–1. Additionally, all peptides had no toxicity to three lines of human cells as well as to zebrafish larvae and embryos. Thus, these peptides have potential activity against SARS-CoV-2, making them promising to develop new drugs to inhibit cell infection by SARS-CoV-2.

Synergistic Antibiofilm Activity between Synthetic Peptides and Ciprofloxacin against Staphylococcus aureus

“…This is an exciting result because it reinforces the potential of peptides as adjuvants in drug formulations to treat infections caused by S. aureus. As revealed in other studies, the peptides used in this study were not toxic to human cells, and zebrafish embryos strengthen the clinical application of peptides [10,12,22].…”

“…The synthetic peptides used in this work have already shown antimicrobial activity against many human pathogens, such as dermatophyte fungi, pathogenic yeasts, SARS-CoV-2, and bacteria such as S. aureus itself [10,12,[20][21][22]. The hypothesis behind this work was whether these peptides could inhibit the formation or even reduce S. aureus biofilm biomass alone or in combination with ciprofloxacin.…”

Can Probiotics, Particularly Limosilactobacillus fermentum UCO-979C and Lacticaseibacillus rhamnosus UCO-25A, Be Preventive Alternatives against SARS-CoV-2?

“…Ever since the successful results obtained with peptide hormones in treating diseases, such as in the case of insulin, and considering their lower costs as well as easier production, the market of peptide drugs and vaccines has been increasing, with more than 150 peptides being under development [ 93 ]. In this context, several studies have focused on determining the efficacy of a diversity of peptides, both natural and synthetic, to treat COVID-19 [ 94 , 95 , 96 ]. Results with respect to either the inhibition of some essential SARS-CoV-2 proteins, such as the main protease, or to the antagonism against the spike–ACE2 interaction, have been shown to be promising [ 95 , 96 ].…”

Pragmatic Coarse-Graining of Proteins: Models and Applications

“…PEP-FOLD can be used for de novo modeling of short peptides using Markov state modeling and short MD simulations that generate an ensemble of representative conformations. Examples of PEP-FOLD applications include the structure prediction and the sampling of conformational space of viral antigen epitopes, such as in the SARS CoV-2 or the Zika virus. − In such studies, molecular simulations are usually combined with immunoinformatics methods that allow the determination of potential epitopes for targeting. PEP-FOLD has also been used to predict the structures of drug-like peptides and cellular target epitopes in cancer research. , …”