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Surfactin-like lipopeptides from Bacillus clausii efficiently bind to spike glycoprotein of SARS-CoV-2
Piyush Baindara1, Trinath Chowdhury2, Dinata Roy3
1Department of Radiation Oncology, University of Missouri, Columbia, MO, USA.
Insights
A novel surfactin-like lipopeptide from Bacillus clausii TS effectively inhibits SARS-CoV-2 spike protein binding. This discovery offers a promising new avenue for developing antiviral therapies against COVID-19 and emerging variants.
Area of Science:
- Biochemistry
- Microbiology
- Virology
Background:
- COVID-19 remains a global health threat despite vaccines.
- Bio-surfactants exhibit antiviral properties and may offer alternative treatments.
- SARS-CoV-2 spike protein is a key target for antiviral drug development.
Purpose of the Study:
- To isolate and characterize a lipopeptide with potential antiviral activity against SARS-CoV-2.
- To investigate the binding interaction between the purified lipopeptide and the SARS-CoV-2 spike protein.
- To evaluate the therapeutic potential of the lipopeptide for COVID-19 treatment.
Main Methods:
- Isolation and purification of a lipopeptide from *Bacillus clausii* TS.
- MALDI analysis for molecular weight determination.
- Competitive ELISA, Isothermal Titration Calorimetry (ITC), molecular docking, dynamics, and simulation experiments to assess binding and inhibition of SARS-CoV-2 spike protein (S1) and its receptor binding domain (RBD).
Main Results:
- A surfactin-like lipopeptide with a molecular weight of 1037 Da was isolated.
- The lipopeptide demonstrated efficient binding and inhibition of the SARS-CoV-2 spike (S1) protein.
- ITC assay confirmed inhibitory binding with a binding constant of 1.78 × 10-4 M-1.
- Molecular modeling studies validated the inhibitory interaction with the S1 protein and RBD.
Conclusions:
- The purified surfactin-like lipopeptide shows significant potential as an antiviral agent against SARS-CoV-2.
- This lipopeptide is a promising candidate for developing novel spike protein-targeting drugs for COVID-19.
- Further research into surfactin-based therapies is warranted for combating current and future viral threats.
Abstract:
The coronavirus disease 2019 (COVID-19) rapidly spread across the globe, infecting millions and causing hundreds of deaths. It has been now around three years but still, it remained a serious threat worldwide, even after the availability of some vaccines. Bio-surfactants are known to have antiviral activities and might be a potential alternative for the treatment of SARS-CoV-2 infection. In the present study, we have isolated and purified, a surfactin-like lipopeptide produced by a probiotic bacterial strain Bacillus clausii TS. Upon purification and characterization with MALDI analysis, the molecular weight of the lipopeptide is confirmed as 1037 Da (similar to surfactin C) which is known to have antiviral activities against various enveloped viruses. Purified surfactin-like lipopeptide showed efficient binding and inhibition of SARS-CoV-2 spike (S1) protein, revealed by competitive ELISA assay. Further, we have explored the complete thermodynamics of the inhibitory binding of surfactin-like lipopeptide with S1 protein using isothermal titration calorimetric (ITC) assay. ITC results are in agreement with ELISA with a binding constant of 1.78 × 10-4 M-1. For further validation of the inhibitory binding of surfactin-like lipopeptide with S1 protein and its receptor binding domain (RBD), we performed molecular docking, dynamics, and simulation experiments. Our results suggested that surfactin could be a promising drug agent for the spike protein targeting drug development strategy against SARS-CoV-2 and other emerging variants.Communicated by Ramaswamy H. Sarma.
