Screening of camphene as a potential inhibitor targeting SARS-CoV-2 various structural and functional mutants: Through reverse docking approach

Background: SARS-CoV was first identified in 2003 but SARS-CoV-2, which gained its recognition again in 2019 as COVID-19, has been a crucial threat worldwide and has caused more death rates than the SARS-CoV but till now no confined treatments are available. The present study aimed to investigate the efficacy of camphene against various structural and functional mutants of SARS-CoV-2 using reverse docking protocol. Methods: To investigate the efficacy of camphene as a potential antiviral drug against COVID-19, against of all possible target proteins in SARS-CoV-2, which could lead to a new platform for drug discovery. Reverse pharmacology (Reverse docking) approach was performed, which involved docking of camphene and 20 structural and non-structural proteins (NSPs) of SARS-CoV-2 performed using maestro 12.8 of Schrödinger. Results: The results were evaluated since the minimum binding energy obtained after docking and camphene was effective against most of the proteins responsible for SARS-CoV-2, but camphene showed greater efficacy against the main protease (protease 9), which is main functional protein of SARS-CoV-2. Hence, the study proves that camphene can be a good drug candidate for different mutants of SARS-CoV-2. Conclusion: Protease 9, which is the main functional protein of SARS-CoV-2, expressed the best binding affinity with camphene having the minimum binding energy (-5.616). Hence, it is concluded that camphene could be the drug contender against protease 9 as it is a more potent target in SARS-CoV-2. This could be a major finding, as camphene is related to camphor, which is already very beneficial against many respiratory problems.