A molecular docking study revealed that synthetic peptides induced conformational changes in the structure of SARS-CoV-2 spike glycoprotein, disrupting the interaction with human ACE2 receptor.

The global outbreak of COVID-19 (Coronavirus Disease 2019) caused by SARS-CoV-2 (Severe Acute Respiratory Syndrome caused by Coronavirus 2) began in December 2019. Its closest relative, SARS-CoV-1, has a slightly mutated Spike (S) protein, which interacts with ACE2 receptor in human cells to start the infection. So far, there are no vaccines or drugs to treat COVID-19. So, research groups worldwide are seeking new molecules targeting the S protein to prevent infection by SARS-CoV-2 and COVID-19 establishment. We performed molecular docking analysis of eight synthetic peptides against SARS-CoV-2 S protein. All interacted with the protein, but Mo-CBP3-PepII and PepKAA had the highest affinity with it. By binding to the S protein, both peptides led to conformational alterations in the protein, resulting in incorrect interaction with ACE2. Therefore, given the importance of the S protein-ACE2 interaction for SARS-CoV-2 infection, synthetic peptides could block SARS-CoV-2 infection. Moreover, unlike other antiviral drugs, peptides have no toxicity to human cells. Thus, these peptides are potential molecules to be tested against SARS-CoV-2 and to develop new drugs to treat COVID-19.