In silico studies on milk derived peptides as potential inhibitors against SARS CoV-2 spike protein receptor binding domain

Abstract

\n COVID-19 (Corona Virus Infected Diseases-19) is caused by a strain of coronavirus called SARS-CoV-2 (Severe acute respiratory syndrome coronavirus 2). There’s no permanent diagnosis available till date to combat the disease. The viral infection in humans is initiated by binding of RBD (receptor binding domain) of spike protein to human angiotensin-converting enzyme 2 (hACE2) receptor protein. In this computational study, milk-derived peptides are screened against Receptor Binding Domain (RBD) of spike protein of the virus. Milk is considered as one of the most nutrient-rich liquid foods having several antibacterial and antiviral activities. Milk derived peptides including Casein and Whey derived peptides are known to have profound anti-viral and immunomodulatory activities. After extensive literature search, some peptides having anti-viral activities against different viruses, are shortlisted for this study and their three-dimensional structures are modelled for protein-peptide docking against SARS-CoV-2 spike protein RBD. After performing protein-peptide docking and protein-protein docking using different servers such as HPEPDOCK, FIREDOCK, HADDOCK, HDOCK, it has been observed that in presence of the peptides, the interaction between spike RBD and hACE2 has been reasonably decreased, which implies that milk-derived peptides can be potential peptide-inhibitors against the RBD of the virus along with other medications. Further studies on milk-derived peptides should be performed to develop peptide drugs based on milk-derived peptides.