In Silico Identification and Docking-Based Drug Repurposing Against the Main Protease of SARS-CoV-2, Causative Agent of COVID-19
<div>The rapidly enlarging COVID-19 pandemic caused by novel SARS-coronavirus 2 is a global</div><div>public health emergency of unprecedented level. Therefore the need of a drug or vaccine that</div><div>counter SARS-CoV-2 is an utmost requirement at this time. Upon infection the ssRNA genome</div><div>of SARS-CoV-2 is translated into large polyprotein which further processed into different</div><div>nonstructural proteins to form viral replication complex by virtue of virus specific proteases:</div><div>main protease (3-CL protease) and papain protease. This indispensable function of main protease</div><div>in virus replication makes this enzyme a promising target for the development of inhibitors and</div><div>potential treatment therapy for novel coronavirus infection. The recently concluded α-ketoamide</div><div>ligand bound X-ray crystal structure of SARS-CoV-2 Mpro (PDB ID: 6Y2F) from Zhang et al.</div><div>has revealed the potential inhibitor binding mechanism and the determinants responsible for</div><div>involved molecular interactions. Here, we have carried out a virtual screening and molecular</div><div>docking study of FDA approved drugs primarily targeted for other viral infections, to investigate</div><div>their binding affinity in Mpro active site. Virtual screening has identified a number of antiviral</div><div>drugs, top ten of which on the basis of their bending energy score are further examined through </div><div>molecular docking with Mpro. Docking studies revealed that drug Lopinavir-Ritonavir, Tipranavir</div><div>and Raltegravir among others binds in the active site of the protease with similar or higher</div><div>affinity than the crystal bound inhibitor α-ketoamide. However, the in-vitro efficacies of the drug</div><div>molecules tested in this study, further needs to be corroborated by carrying out biochemical and</div><div>structural investigation. Moreover, this study advances the potential use of existing drugs to be</div><div>investigated and used to contain the rapidly expanding SARS-CoV-2 infection.</div>