Kobophenol A Inhibits Binding of Host ACE2 Receptor with Spike RBD Domain of SARS-CoV-2, a Lead Compound for Blocking COVID-19

In the search for inhibitors of COVID-19, we have targeted the interaction between the human angiotensin-converting enzyme 2 (ACE2) receptor and the spike receptor binding domain (S1-RBD) of SARS-CoV-2. Virtual screening of a library of natural compounds identified Kobophenol A as a potential inhibitor. Kobophenol A was then found to block the interaction between the ACE2 receptor and S1-RBD in vitro with an IC50 of 1.81 +/- 0.04 mu M and inhibit SARS-CoV-2 viral infection in cells with an EC50 of 71.6 mu M. Blind docking calculations identified two potential binding sites, and molecular dynamics simulations predicted binding free energies of -19.0 +/- 4.3 and -24.9 +/- 6.9 kcal/mol for Kobophenol A to the spike/ACE2 interface and the ACE2 hydrophobic pocket, respectively. In summary, Kobophenol A, identified through docking studies, is the first compound that inhibits SARS-CoV-2 binding to cells through blocking S1-RBD to the host ACE2 receptor and thus may serve as a good lead compound against COVID-19.

Automated summary

The study revealed that Kobophenol A, identified through virtual screening, could potentially serve as an inhibitor for COVID-19 by blocking the interaction between the virus and cells, inhibiting viral infection. Molecular dynamics simulations indicated strong affinity of Kobophenol A to the ACE2 receptor, making it a promising compound for antiviral therapy.