Identification of Main Protease of Coronavirus SARS-CoV-2 (Mpro)Inhibitors from Melissa officinalis

Author(s):  
Olusola O. Elekofehinti ◽  
Opeyemi Iwaloye ◽  
Courage D. Famusiwa ◽  
Olanrewaju Akinseye ◽  
Joao B. T. Rocha

Background: he recent outbreak of Coronavirus SARS-CoV-2 (Covid-19) which has rapidly spread around the world in about three months with tens of thousands of deaths recorded so far is a global concern. An urgent need for potential therapeutic intervention is of necessity. Mpro is an attractive druggable target for the development of anti-COVID-19 drug development. Compounds previously characterized from Melissa officinalis were queried against main protease of coronavirus SARS-CoV-2 using computational approach. Results: Melitric acid A and salvanolic acid A had higher affinity than lopinavir and ivermectin using both AutodockVina and XP docking algorithms. The computational approach was employed in the generation of QSAR model using automated QSAR, and in the docking of ligands from Melissa officinalis with SARS-CoV-2 Mpro inhibitors. The best model obtained was KPLS_Radial_28 (R2 = 0.8548 and Q2=0.6474, and was used in predicting the bioactivity of the lead compounds. Molecular mechanics based MM-GBSA confirmed salvanolic acid A as the compound with the highest free energy and predicted bioactivity of 4.777; it interacted with His-41 of the catalytic dyad (Cys145-His41) of SARS-CoV-2 main protease (Mpro), as this may hinder the cutting of inactive viral protein into active ones capable of replication. Conclusion: Salvanolic acid A can be further evaluated as potential Mpro inhibitor.

2020 ◽  
Author(s):  
Micael Davi Lima de Oliveira ◽  
Kelson Mota Teixeira de Oliveira

According to the World Health Organisation, until 16 June, 2020, the number of confirmed and notified cases of COVID-19 has already exceeded 7.9 million with approximately 434 thousand deaths worldwide. This research aimed to find repurposing antagonists, that may inhibit the activity of the main protease (Mpro) of the SARS-CoV-2 virus, as well as partially modulate the ACE2 receptors largely found in lung cells, and reduce viral replication by inhibiting Nsp12 RNA polymerase. Docking molecular simulations were performed among a total of 60 structures, most of all, published in the literature against the novel coronavirus. The theoretical results indicated that, in comparative terms, paritaprevir, ivermectin, ledipasvir, and simeprevir, are among the most theoretical promising drugs in remission of symptoms from the disease. Furthermore, also corroborate indinavir to the high modulation in viral receptors. The second group of promising drugs includes remdesivir and azithromycin. The repurposing drugs HCQ and chloroquine were not effective in comparative terms to other drugs, as monotherapies, against SARS-CoV-2 infection.


Author(s):  
Farzaneh Shobeirian

Background: Coronaviruses are non-segmented enveloped positive-sense single-strand RNA viruses, and COVID-19 is the seventh known coronavirus, infecting humans. Objective: As the COVID-19 continued to spread the world wildly, every radiologist or clinician needs to be familiar with its imaging findings. Methods: In this study, we reviewed available studies to provide a comprehensive statement on COVID-19 imaging findings. Results: Ground-glass opacities, linear opacities, interlobular septal thickening, consolidation, and Crazy-paving patterns are the most frequent findings in computed tomography (CT) of lungs in patients with COVID-19 pneumonia, which are mostly bilateral, multifocal, and peripheral. Staff needs to follow some rules to reduce infection transmission. Conclusion: COVID-19 pneumonia is a new global concern which has many unknown features. In this article, the radiologic characteristics of COVID-19 pneumonia are discussed. We also discussed appropriate protective measures that the radiology team should be aware of.


2021 ◽  
Vol 14 (4) ◽  
pp. 357
Author(s):  
Magdi E. A. Zaki ◽  
Sami A. Al-Hussain ◽  
Vijay H. Masand ◽  
Siddhartha Akasapu ◽  
Sumit O. Bajaj ◽  
...  

Due to the genetic similarity between SARS-CoV-2 and SARS-CoV, the present work endeavored to derive a balanced Quantitative Structure−Activity Relationship (QSAR) model, molecular docking, and molecular dynamics (MD) simulation studies to identify novel molecules having inhibitory potential against the main protease (Mpro) of SARS-CoV-2. The QSAR analysis developed on multivariate GA–MLR (Genetic Algorithm–Multilinear Regression) model with acceptable statistical performance (R2 = 0.898, Q2loo = 0.859, etc.). QSAR analysis attributed the good correlation with different types of atoms like non-ring Carbons and Nitrogens, amide Nitrogen, sp2-hybridized Carbons, etc. Thus, the QSAR model has a good balance of qualitative and quantitative requirements (balanced QSAR model) and satisfies the Organisation for Economic Co-operation and Development (OECD) guidelines. After that, a QSAR-based virtual screening of 26,467 food compounds and 360 heterocyclic variants of molecule 1 (benzotriazole–indole hybrid molecule) helped to identify promising hits. Furthermore, the molecular docking and molecular dynamics (MD) simulations of Mpro with molecule 1 recognized the structural motifs with significant stability. Molecular docking and QSAR provided consensus and complementary results. The validated analyses are capable of optimizing a drug/lead candidate for better inhibitory activity against the main protease of SARS-CoV-2.


mBio ◽  
2020 ◽  
Vol 11 (4) ◽  
Author(s):  
Shin-ichiro Hattori ◽  
Nobuyo Higshi-Kuwata ◽  
Jakka Raghavaiah ◽  
Debananda Das ◽  
Haydar Bulut ◽  
...  

ABSTRACT We assessed various newly generated compounds that target the main protease (Mpro) of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and various previously known compounds reportedly active against SARS-CoV-2, employing RNA quantitative PCR (RNA-qPCR), cytopathicity assays, and immunocytochemistry. Here, we show that two indole-chloropyridinyl-ester derivatives, GRL-0820 and GRL-0920, exerted potent activity against SARS-CoV-2 in cell-based assays performed using VeroE6 cells and TMPRSS2-overexpressing VeroE6 cells. While GRL-0820 and the nucleotide analog remdesivir blocked SARS-CoV-2 infection, viral breakthrough occurred. No significant anti-SARS-CoV-2 activity was found for several compounds reportedly active against SARS-CoV-2 such as lopinavir, nelfinavir, nitazoxanide, favipiravir, and hydroxychroloquine. In contrast, GRL-0920 exerted potent activity against SARS-CoV-2 (50% effective concentration [EC50] = 2.8 μM) and dramatically reduced the infectivity, replication, and cytopathic effect of SARS-CoV-2 without significant toxicity as examined with immunocytochemistry. Structural modeling shows that indole and chloropyridinyl of the derivatives interact with two catalytic dyad residues of Mpro, Cys145 and His41, resulting in covalent bonding, which was verified using high-performance liquid chromatography–mass spectrometry (HPLC/MS), suggesting that the indole moiety is critical for the anti-SARS-CoV-2 activity of the derivatives. GRL-0920 might serve as a potential therapeutic for coronavirus disease 2019 (COVID-19) and might be optimized to generate more-potent anti-SARS-CoV-2 compounds. IMPORTANCE Targeting the main protease (Mpro) of SARS-CoV-2, we identified two indole-chloropyridinyl-ester derivatives, GRL-0820 and GRL-0920, active against SARS-CoV-2, employing RNA-qPCR and immunocytochemistry and show that the two compounds exerted potent activity against SARS-CoV-2. While GRL-0820 and remdesivir blocked SARS-CoV-2 infection, viral breakthrough occurred as examined with immunocytochemistry. In contrast, GRL-0920 completely blocked the infectivity and cytopathic effect of SARS-CoV-2 without significant toxicity. Structural modeling showed that indole and chloropyridinyl of the derivatives interacted with two catalytic dyad residues of Mpro, Cys145 and His41, resulting in covalent bonding, which was verified using HPLC/MS. The present data should shed light on the development of therapeutics for COVID-19, and optimization of GRL-0920 based on the present data is essential to develop more-potent anti-SARS-CoV-2 compounds for treating COVID-19.


2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Esraa M. O. A. Ismail ◽  
Shaza W. Shantier ◽  
Mona S. Mohammed ◽  
Hassan H. Musa ◽  
Wadah Osman ◽  
...  

The recent outbreak of the highly contagious coronavirus disease 2019 (COVID-19) caused by the novel coronavirus SARS-CoV-2 has created a global health crisis with socioeconomic impacts. Although, recently, vaccines have been approved for the prevention of COVID-19, there is still an urgent need for the discovery of more efficacious and safer drugs especially from natural sources. In this study, a number of quinoline and quinazoline alkaloids with antiviral and/or antimalarial activity were virtually screened against three potential targets for the development of drugs against COVID-19. Among seventy-one tested compounds, twenty-three were selected for molecular docking based on their pharmacokinetic and toxicity profiles. The results identified a number of potential inhibitors. Three of them, namely, norquinadoline A, deoxytryptoquivaline, and deoxynortryptoquivaline, showed strong binding to the three targets, SARS-CoV-2 main protease, spike glycoprotein, and human angiotensin-converting enzyme 2. These alkaloids therefore have promise for being further investigated as possible multitarget drugs against COVID-19.


2021 ◽  
Author(s):  
Mohd. Suhail

<p><a>It has been a great challenge for scientists to develop an anti-covid drug/vaccine with fewer side effects, since the coronavirus began. Of course, the prescription of chiral drugs (chloroquine or hydroxychloroquine) has been proved wrong because these chiral drugs neither kill the virus nor eliminate it from the body, but block SARS-CoV-2 from binding to human cells. Another hurdle in front of the world, is not only the positive test of the patient recovered from coronavirus but also the second wave of Covid 19. Hence, the word demands such a drug or drug combination which not only prevents the entry of SARS-CoV-2 in the human cell but also eliminates it or its material from the body completely. The presented computational study explains (i) why the prescription of chiral drugs was not satisfactory (ii) what types of modification can make their prescription satisfactory (iii) the mechanism of action of chiral drugs (chloroquine and hydroxychloroquine) to block SARS-CoV-2 from binding to human cells, and (iv) the strength of mefloquine to eliminate SARS-CoV-2. As the main protease (M<b><sup>pro</sup></b>) of microbes is considered as an effective target for drug design and development, the binding affinities of mefloquine with the main proteases (M<sup>pros</sup>) of JC virus and SARS-CoV-2, were calculated, and then compared to know the eliminating strength of mefloquine against SARS-CoV-2. The main protease (M<sup>pro</sup>) of JC virus was taken because mefloquine has already shown a tremendous result of eliminating it from the body. The current study includes the docking results and literature data in support of the prescription of a combination of S-(+)-hydroxychloroquine and (+) mefloquine. Besides, the presented study also confirms that the prescription of only hydroxychloroquine would not be so effective as in combined form with mefloquine.</a></p>


2020 ◽  
Author(s):  
Muthu Raj S ◽  
Manohar M ◽  
Mohan M ◽  
Ganesh P ◽  
Marimuthu K

<p>The spread of SARS CoV 2 across the globe rushed the scientific community to find out the potential inhibitor for controlling the viral disease. The main protease (Mpro) or Chymotrypsin protease (3CLpro) is involved in the cleavage of polyproteins, duplication of intracellular materials and release of nonstructural proteins. Cys-His catalytic dyad is located in the SARS-CoV Mpro which is the substrate-binding site located in domains I and II. There are many approved drugs that have their active protease inhibition capability. The targeting of the active site of the main protease is the better option to fight against the viral population. Lopinavir, ritonavir, Remdesivir and Chloroquine are some of the drug candidates considered to be involved in the treatment of SARS CoV 2 under emergency situation as a trial basis. In the present investigation we used lopinavir as a drug to bind the catalytic dyad His41, Cys145 of main protease. The minimum binding of energy of -11.45 kcal/mol observed with the binding of Cys145 and -10.93 kcal/mol was noted with the residue His41. The inhibition constant was also found to be relevant to the binding efficiency of the drug. This is considered to be a model drug target which is initiating the finding of many new drugs to target the current outbreak created by the virus SARS.CoV - 2.</p>


2020 ◽  
Author(s):  
Jian Li ◽  
Xuelan Zhou ◽  
Yan Zhang ◽  
Fanglin Zhong ◽  
Cheng Lin ◽  
...  

AbstractMain protease (Mpro, also known as 3CLpro) has a major role in the replication of coronavirus life cycle and is one of the most important drug targets for anticoronavirus agents. Here we report the crystal structure of main protease of SARS-CoV-2 bound to a previously identified Chinese herb inhibitor shikonin at 2.45 angstrom resolution. Although the structure revealed here shares similar overall structure with other published structures, there are several key differences which highlight potential features that could be exploited. The catalytic dyad His41-Cys145 undergoes dramatic conformational changes, and the structure reveals an unusual arrangement of oxyanion loop stabilized by the substrate. Binding to shikonin and binding of covalent inhibitors show different binding modes, suggesting a diversity in inhibitor binding. As we learn more about different binding modes and their structure-function relationships, it is probable that we can design more effective and specific drugs with high potency that can serve as effect SARS-CoV-2 anti-viral agents.


Author(s):  
Jamie A. Kelly ◽  
Alexandra N. Olson ◽  
Krishna Neupane ◽  
Sneha Munshi ◽  
Josue San Emeterio ◽  
...  

Abstract17 years after the SARS-CoV epidemic, the world is facing the COVID-19 pandemic. COVID-19 is caused by a coronavirus named SARS-CoV-2. Given the most optimistic projections estimating that it will take over a year to develop a vaccine, the best short-term strategy may lie in identifying virus-specific targets for small molecule interventions. All coronaviruses utilize a molecular mechanism called −1 PRF to control the relative expression of their proteins. Prior analyses of SARS-CoV revealed that it employs a structurally unique three-stemmed mRNA pseudoknot to stimulate high rates of −1 PRF, and that it also harbors a −1 PRF attenuation element. Altering −1 PRF activity negatively impacts virus replication, suggesting that this molecular mechanism may be therapeutically targeted. Here we present a comparative analysis of the original SARS-CoV and SARS-CoV-2 frameshift signals. Structural and functional analyses revealed that both elements promote similar rates of −1 PRF and that silent coding mutations in the slippery sites and in all three stems of the pseudoknot strongly ablated −1 PRF activity. The upstream attenuator hairpin activity has also been functionally retained. Small-angle x-ray scattering indicated that the pseudoknots in SARS-CoV and SARS-CoV-2 had the same conformation. Finally, a small molecule previously shown to bind the SARS-CoV pseudoknot and inhibit −1 PRF was similarly effective against −1 PRF in SARS-CoV-2, suggesting that such frameshift inhibitors may provide promising lead compounds to counter the current pandemic.


2018 ◽  
Vol 66 (3) ◽  
pp. 255 ◽  
Author(s):  
Thaís A. P. Gonçalves ◽  
Julia Sonsin-Oliveira ◽  
Silvana Nisgoski ◽  
Carmen R. Marcati ◽  
Adriano W. Ballarin ◽  
...  

Brazil has one of the richest biodiversities in the world. The Brazilian savanna is a hotspot for conservation priorities and its deforestation is of global concern. Conservation in this biome is threatened by unsustainable use of forests, such as illegal logging for charcoal production. Thus, government agents need to verify whether charcoal loads follow the Document of Forestry Origin (DOF). To improve charcoal identification, our study presents the microscopic description of 10 Cerrado species and provides an identification key to aid government agents during surveillance. We analysed charcoal samples with a scanning electron microscope. The method of carbonisation simulated real conditions. We chose species with similar wood anatomy (sparse axial parenchyma and narrow rays), which increases misidentification by forest controllers because of their difficulty to identify these features. Also, paratracheal scanty, diffuse and diffuse-in-aggregates parenchyma were harder to recognise in charcoal than in wood. Other features, such as vessels, rays and abundant axial parenchyma, were easily identified. The present work can be used as a part of a charcoal anatomy database focussed on preventing deforestation in Brazil and in other countries with similar problems.


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