A Review of Human Coronaviruses' Receptors: The Host-Cell Targets for the Crown Bearing Viruses.

A novel human coronavirus prompted considerable worry at the end of the year 2019. Now, it represents a significant global health and economic burden. The newly emerged coronavirus disease caused by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is the primary reason for the COVID-19 global pandemic. According to recent global figures, COVID-19 has caused approximately 243.3 million illnesses and 4.9 million deaths. Several human cell receptors are involved in the virus identification of the host cells and entering them. Hence, understanding how the virus binds to host-cell receptors is crucial for developing antiviral treatments and vaccines. The current work aimed to determine the multiple host-cell receptors that bind with SARS-CoV-2 and other human coronaviruses for the purpose of cell entry. Extensive research is needed using neutralizing antibodies, natural chemicals, and therapeutic peptides to target those host-cell receptors in extremely susceptible individuals. More research is needed to map SARS-CoV-2 cell entry pathways in order to identify potential viral inhibitors.

The anti-HCV, Sofosbuvir, versus the anti-EBOV Remdesivir against SARS-CoV-2 RNA dependent RNA polymerase in silico.

Coronavirus diseases 2019 (COVID-19) are seriously affecting human health all over the world. Nucleotide inhibitors have promising results in terms of its efficacy against different viral polymerases. In this study, detailed molecular docking and dynamics simulations are used to evaluate the binding affinity of a clinically approved drug, sofosbuvir, with the solved structure of the viral protein RNA-dependent RNA polymerase (RdRp) and compare it to the clinically approved drug, Remdesivir. These drugs are docked onto the three-dimensional structure of the nsp12 protein of SARS-CoV-2, which controls the polymerization process. Hence, it is considered one of the primary therapeutic targets for coronaviruses. Sofosbuvir is a drug that is currently used for HCV treatment; therefore, HCV RdRp is used as a positive control protein target. The protein dynamics are simulated for 100 ns, while the binding is tested during different dynamics states of the SARS-CoV-2 RdRp. Additionally, the drug-protein complexes are further simulated for 20 ns to explore the binding mechanism. The interaction of SARS-CoV-2 RdRp as a target with the active form of sofosbuvir as a ligand demonstrates binding effectiveness. One of the FDA-approved antiviral drugs, such as sofosbuvir, can help us in this mission, aiming to limit the danger of COVID-19. Sofosbuvir was found to bind nsp12 with comparable binding energies to that of Remdesivir, which has been reported for its potential against COVID-19 RdRp and is currently approved by the FDA.

Novel guanosine derivatives against MERS CoV polymerase: An in silico perspective.

The Middle East Respiratory Syndrome Coronavirus (MERS CoV), also termed camel flu, is a new viral infection that first reported in the year 2012 in the Middle East region and further spread during the last seven years. MERS CoV is characterized by its high mortality rate among different human coronaviruses. MERS CoV polymerase shares more than 20% sequence identity with the Hepatitis C Virus (HCV) Non-structural 5b (NS5b) RNA dependent RNA polymerase (RdRp). Despite the low sequence identity, the active site is conserved between the two proteins, with two consecutive aspartates that are crucial in the nucleotide transfer reaction. In this study, seven nucleotide inhibitors have been tested against MERS CoV RdRp using molecular modeling and docking simulations, from which four are novel compounds. Molecular Dynamics Simulation for 260 nanoseconds is performed on the MERS CoV RdRp model to test the effect of protein dynamics on the binding affinities to the tested nucleotide inhibitors. Results support the hypothesis of using the anti-polymerases (Anti-HCV drugs) against MERS CoV RdRp as a potent candidates. Besides four novel compounds are suggested as a seed for high performance inhibitors against MERS CoV RdRp.Communicated by Ramaswamy H. Sarma.