ABSTRACT
Background and Objective: An enzyme that inhibits the receptor could make it more difficult for coronavirus to reach cells. The key protease necessary for coronavirus proteolytic maturation is the recognized coronavirus 3-chymotrypsin-like protease 3CLpro, also known as Mpro. This Mpro is needed for immune control and the cleavage of the polyproteins pp1a and pp1ab, making it a promising target for anti-COVID-19 drugs. As a result, inhibiting the Mpro enzyme inhibits viral maturation. Bioactive constituents obtained from some selected indigenous plants of India, which have been reported to have antiviral potential, were subjected to virtual screening against ACE-2 and Mpro in the current study. Materials and Methods: Cresset's Flare 4.0 was used to establish the 3-D structure of all the compounds. Complete optimizations of these constructed structures were carried out. While performing the minimization, the spin state of the wave function was set to the singlet and standard SCF convergence was used for optimization, all other parameters were left at their default values. The Protein Data Bank (https://www.rcsb.org) was used to download the 3-D structures of Mpro from COVID-19 (PDB ID 6LU7) and ACE-2 receptor from Human (PDB ID 1R4L). Results: The findings show that these phytochemicals can bind to ACE-2 and Mpro more effectively as compared to reference compounds and act as inhibitors. Conclusion: The findings of virtual screening of these bioactive constituents revealed that most of them are more active than the reference compounds. Therefore, they could be used to produce antiviral drugs against Coronavirus in the future.
ABSTRACT
An outbreak of coronavirus pneumonia was firstly documented in Wuhan, Hubei Province, China (December 2019), with an indication of human-to-human transmission. The causative agent identified for coronavirus disease 2019 (COVID-19) is the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). America, Italy, India, and Africa became new venues of COVID infection;the overall data of patients and death is increasing day by day. Generally inplace of most of the infected people develop respiratory symptoms (throat pain, cough, etc.), fever, and chest opacity on CT scan and X-ray. A few numbers of suspected persons are found asymptomatic;they may serve as carriers for infection. As a point of care, the patient diagnosis is compulsory, and only the diagnosis can provide a real-time condition of patients and can be helpful in arresting the spreading of the infection. In the present chapter, we focused on illustrating various diagnostic techniques that have been employed by the world for the detection of the coronavirus. The diagnostic techniques are categorized into molecular and serologic assay techniques. The nucleic acid is detected in molecular assay, whereas the serologic assay uses antigen-antibody reaction. © Springer Nature Switzerland AG 2021.