Revealing Potential Binding Affinity of FDA Approved Therapeutics Targeting Main Protease (3CLpro) in Impairing Novel Coronavirus (SARSCoV- 2) Replication that Causes COVID-19

Background:

Spread of COVID-19 attains a crucial transition in reveling its pandemic across the boundaries. In combating the infection caused by SARS-CoV-2, there is a spectrum of ideal strategies that have been adopted globally, of which repurposing of approved drugs considerably having high clinical relevance. 3-chymotrypsin-like protease (3CL pro) is considered to be the potential target for the researchers as it is highly essential for cleavage of polyprotein to get 16 nonstructural proteins (called nsp1-nsp16). These proteins are highly essential for viral replication and hence become a primary target for enzyme inhibitors. 3CL pro, having a structural projectile helical chain with biologically active site involved in processing viral polyproteins that are evolved from RNA genome translation.

Objective:

The major objective of the present investigation is to evaluate the enzyme inhibition potential of FDA approved therapeutic leads in targeting 3CLpro that medicates the viral replication.

Methods:

Docking calculations were carried out for an array of FDA approved molecules which leads to a notable few molecules such as Emtricitabine, Oseltamivir, Ganciclovir, Chloroquine, Baricitinib, Favipiravir, Lopinavir, Ritonavir, Remdesivir, Ribavirin, Tenofovir, Umifenovir, Carbapenam, Ertapenem and Imipenam which have both specificity and selectivity in terms of binding efficiency against 3CL proenzyme.

Results:

A combinatorial evaluation employing in-silico screening shows a major lead for remdesivir which possesses a substantial affinity to 3CL pro binding on core amino acid residues, such as Leu 27, His 41, Gly 143, Cys 145, His 164, Met 165, Glu 166, Pro 168 and His 172 which share the biological significance in mediating enzymatic action. Results of docking simulation by Autodock over a host of FDA approved molecules show high degree of selectivity and specificity in the increasing order of binding capacity; Remdesivir> Ertapenem> Imipenam> Tenofovir> Umifenovir> Chloroquine> Lopinavir> Ritonavir> Emtricitabine> Ganciclovir> Baricitinib> Ribavirin>Oseltamivir>Favipiravir> Carbapenam.

Conclusion:

Till date, there is no known cure attained for treating COVID-19 infection. In conclusion, lead molecules from already approved sources provoke promising potential which grabs the attention of the clinicians in availing potential therapeutic candidate as a drug of choice in the clinical management of COVID-19 time-dependently.

Current Strategies and Approaches in Combating SARS-CoV-2 Virus that Causes COVID-19

Abstract:

The pandemic spread of severe acute respiratory syndrome coronavirus (SARS-CoV-2) that causes COVID-19 calls for global health emergency with wide prevalence across 94 countries, and around 3073 deaths reported in china on 7th March 2020 which created red alert zone in the country. It was further noticed other than China, countries like the republic of Korea ranked first with 6767 cases, Italy with 4747 and Iran with 3513 cases. The spread of COVID-19 made a historical transition between December 2019 to March 2020 by extending the paradigm to a newer territory every day with the highest predicted reproductive number <2. Hence, while combating the epidemic spread, there are spectra of strategies that require crucial validation, some of which include drug repurposing, enzyme inhibition, target drug delivery etc. Among these, the category of drugs called enzyme inhibitors has a unique opportunity in the process of new drug discovery as these enzymes possess structural versatility starting from the host viral interface and up to the release of a new virus. Drugs entrapped within liposomes are highly effective against intracellular microorganisms as per published observations. Regulatory authorities like World Health Organization (WHO) and Centre for disease control and prevention (CDC) strongly recommend the need for the PPE’s like N95 respirator to avoid person to person contact. In this context, Electrospun Nanofiber Technology (ENT) offers ultrathin fibres (20-200 nm) with close proximity of 99.97% of high efficient air filtration. Fabrication of ultrafine nano mask by utilizing electospun technology will surely benefit millions of people in a time-dependent manner.

Effect of Ru-Mn redox interactions on the hole carrier density in pulsed electron deposited La(1-x)Pb(x)Mn(0.8)Ru(0.2)O(3) (0.2≤x≤0.4) thin films

Pulsed electron deposited thin films of Ru substituted La(1-x)Pb(x)Mn(0.8)Ru(0.2)O(3) (0.2≤x≤0.4) show an increase in the magneto-resistance ratio by ∼5-15% at the respective metal to insulator transition (T(MIT)) temperature when compared to the parent La(0.6)Pb(0.4)MnO(3) thin film. A systematic decrease in T(MIT) is observed from ∼310 to ∼260 K when the hole (Pb) concentration varies from 40 to 20% with constant 20% Ru substitution at the Mn site. The x-ray rocking curve and high-resolution transmission electron microscopy (HRTEM) images of the thin films suggest that Ru occupies the Mn site and shows epitaxial growth of the films on the LaAlO(3) (LAO) substrate. Transport and magneto-resistive properties show that Ru substitution maintains a considerable hole carrier density (due to Mn(4+):t(2g)(3)e(g)(0)/Ru(5+):t(2g)(3)e(g)(0)) even for La(0.8)Pb(0.2)Mn(0.8)Ru(0.2)O(3) (8282) composition, which influences the double exchange interactions.

Magnetism and magnetotransport in sonochemically-prepared amorphous Co(100-x)Pt(x) nanoalloys

Amorphous nanoalloys of Co(100-x)Pt(x) (0 < or = x < or = 50) prepared sonochemically exhibit a negative magnetotransport effect, showing a maximum for platinum volume fraction of 10%. The oscillatory peak maxima observed in x = 30 composition for residual resistivity, rho0 and Tmin corresponds to the peak minima for the negative MR% in the range of compositions studied. We observe that in weakly exchange coupled amorphous alloys, the local magnetic order at Tmin and the disorder effects observed from rho0 become crucial.