Original Article

In Silico Comparison of Separate or Combinatorial Effects of Po-tential Inhibitors of the SARS-CoV-2 Binding Site of ACE2


Background: The COVID-19 is a pandemic viral infection with a high morbidity rate, leading to many worldwide deaths since the end of 2019. The RBD (Receptor Binding Domain) of SARS-CoV-2 through its spike utilizes several host molecules to enter host cells. One of the most important ones is the angiotensin-converting enzyme 2 (ACE2), an enzyme normally engaged in renin angiotensin pathway and is responsible for hypertension regulation. As different articles have analyzed separate compounds which can bind ACE2 as the potential virus entry blockers, and each one with a different molecular docking algorithm, in this study we compared all candidate compounds individually as well as their combinations using a unique validated software to introduce most promising ones.

Methods: We collected and prepared a list of all available compounds which potentially can inhibit RBD binding site of the ACE2 from different studies and then reanalyzed and compared them using the Patchdock (ver. 1.3) as a suitable molecular docking algorithm for analysis of separate compounds or their combinations.

Results: Saikosaponin A (e.g. in Bupleurum chinense), Baicalin (e.g. in several species in the genus Scutellaria), Glycyrrhizin (Glycyrrhiza glabra), MLN-4760 and Umifenovir better occupied ACE2 to inhibit viral RBD binding and are suggested as the top five inhibitors of the SARS-CoV-2 binding site of ACE2. Their combinatory effects were also inspiring concurrent ACE2 blockade.

Conclusion: The results propose greatest compounds and their combinatory anti-SARS-CoV-2 effects in order to decrease the time and expenses required for further experimental designs.

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IssueVol 50 No 5 (2021) QRcode
SectionOriginal Article(s)
DOI https://doi.org/10.18502/ijph.v50i5.6120
Compound COVID-19 Inhibitor SARS-CoV-2 Receptor binding domain

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How to Cite
Shakhsi-Niaei M, Heidari Soureshjani E, Babaheydari A. In Silico Comparison of Separate or Combinatorial Effects of Po-tential Inhibitors of the SARS-CoV-2 Binding Site of ACE2. Iran J Public Health. 50(5):1028-1036.