Synthetic Peptide Derived from Scorpion Venom Displays Minimal Toxicity and Anti-infective Activity in an Animal Model.
Cyntia Silva OliveiraMarcelo Der Torossian TorresCibele Nicolaski PedronViviane Brito AndradePedro Ismael SilvaFernanda Dias Silvade la Fuente-Nunez CesarVani Xavier OliveiraPublished in: ACS infectious diseases (2021)
Multidrug-resistant bacteria represent a global health problem increasingly leading to infections that are untreatable with our existing antibiotic arsenal. Therefore, it is critical to identify novel effective antimicrobials. Venoms represent an underexplored source of potential antibiotic molecules. Here, we engineered a peptide (IsCT1-NH2) derived from the venom of the scorpion Opisthacanthus madagascariensis, whose application as an antimicrobial had been traditionally hindered by its high toxicity. Through peptide design and the knowledge obtained in preliminary studies with single and double-substituted analogs, we engineered IsCT1 derivatives with multiple amino acid substitutions to assess the impact of net charge on antimicrobial activity and toxicity. We demonstrate that increased net charge (from +3 to +6) significantly reduced toxicity toward human erythrocytes. Our lead synthetic peptide, [A]1[K]3[F]5[K]8-IsCT1-NH2 (net charge of +4), exhibited increased antimicrobial activity against Gram-negative and Gram-positive bacteria in vitro and enhanced anti-infective activity in a mouse model. Mechanism of action studies revealed that the increased antimicrobial activity of our lead molecule was due, at least in part, to its enhanced ability to permeabilize the outer membrane and depolarize the cytoplasmic membrane. In summary, we describe a simple method based on net charge tuning to turn highly toxic venom-derived peptides into viable therapeutics.
Keyphrases
- gram negative
- multidrug resistant
- global health
- oxidative stress
- drug resistant
- amino acid
- mouse model
- acinetobacter baumannii
- solar cells
- molecular docking
- endothelial cells
- staphylococcus aureus
- healthcare
- room temperature
- oxide nanoparticles
- single cell
- pseudomonas aeruginosa
- ionic liquid
- molecular dynamics simulations