Computational Evidences of Phytochemical Mediated Disruption of PLpro Driven Replication of SARS-CoV-2: A Therapeutic Approach Against COVID-19

Author(s):  
Acharya Balkrishna ◽  
Rashmi Mittal ◽  
Vedpriya Arya

Background:: COVID-19 caused by SARS-CoV-2 has been declared as global pandemic by WHO. Comprehensive analysis of this unprecedented outbreak may help to fight against the disease and may play a pivotal role in decreasing the mortality rate linked with it. Papain like protease (PLpro), a multifunctional polyprotein facilitates the replication of SARS-CoV-2 and evades it from the host immunological response by antagonizing cytokines, interferons and may be considered as potential drug target to combat the current pandemic. Methods:: Natural moieties obtained from medicinal plants were analysed for their potency to target PLpro of SARS-CoV-2 by molecular docking study and were compared with synthetic analogs named as remdesivir, chloroquine and favipiravir. The stability of complexes of top hits was analysed by MD Simulation and interaction energy was calculated. Furthermore, average RMSD values were computed and deepsite ligand binding pockets were predicted using Play Molecule. Drug like abilities of these moieties were determined using ADMET and bond distance between the ligand and active site was assessed to predict the strength of interaction. Results:: Nimbocinol (-7.6 Kcal/mol) and sage (-7.3 Kcal/mol) exhibited maximum BA against PLpro SARS-CoV-2 as evident from molecular docking study which was found to be even better than remdesivir (-6.1 Kcal/mol), chloroquine (-5.3 Kcal/mol) and favipiravir (-5.7 Kcal/mol). Both nimbocinol-PLpro and sage-PLpro SARS-CoV-2 complex exhibited stable conformation during MD Simulation of 101ns at 310 K and potential, kinetic and electrostatic interaction energies were computed which was observed to be concordant with results of molecular docking study. RMSD average values were found to be 0.496 ± 0.015 Å and 0.598 ± 0.023 Å for nimbocinol and sage respectively thus revealing that both the deviation and fluctuations during MD Simulation were observed to be least. Deepsite prediction disclosed that both compounds occupied cryptic pockets in receptor and non-bond distance analysis revealed the formation of hydrogen bonds during ligand-receptor interaction. ADMET exploration further validated the drug like properties of these compounds. Conclusion:: Present study revealed that active constituents of Azadirachta indica and Salvia officinalis can be potentially used to target SARS-CoV-2 by hindering its replication process.

2018 ◽  
Vol 69 (4) ◽  
pp. 837-839
Author(s):  
Cristina Florescu ◽  
Luciana Teodora Rotaru ◽  
Renata Maria Varut ◽  
Gabriela Grigorasi ◽  
Roxana Kostici ◽  
...  

Statins are a class of lipid-lowering medications that reduce cardiovascular disease and mortality in pacients who are at high risk. The molecular docking technique has become an increasingly important tool for drug discovery which help us understand the most stable conformations resulting from ligand-active site of the biological receptor interaction. Partial atomic charges was determined for each molecule showing that the interaction of statins with the receptor is through areas of increased electronic density. The present molecular docking study using Autodock 4.2 was conducted in order to achieve accurate predictions of the best way for bonding and minimum bonding energy, method being applied for five statins drugs as potential inhibitors of HMG-CoA reductase enzyme. The results highlight that simvastatin represent the best inhibitory drug of HMG-CoA reductase enzyme, because the complex simvastatin-enzyme has the lowest binding energy value.


2020 ◽  
Vol 8 (1) ◽  
pp. 221-236 ◽  
Author(s):  
Francisco Nithael Melo Lucio ◽  
José Elieudo Da Silva ◽  
Emanuelle Machado Marinho ◽  
Francisco Rogênio Da Silva Mendes ◽  
Marcia Machado Marinho ◽  
...  

Dengue fever is a serious disease acquired from the Aedes aegypti mosquito present in tropical and subtropical regions, deeply impacting the population's quality of life. Its control requires combating the virus, and the use of substances that do not cause damage to the environment is of fundamental importance. The present work was carried out in silico to perform the structural-electronic characterization of the alkaloid Methylcytisine, a tricyclic quinolizidine alkaloid that has insecticidal activities, identifying the molecular boundary orbitals and descriptors of global chemical reactivity and assessing the inhibitory potential of methylcytisine on NS5 methyltransferase enzyme dengue virus, as well as identifying possible biological targets in humans. Methylcytisine was geometrically optimized through semi-empirical quantum calculations with thermodynamically more stable conformation, characterizing its structure (atoms, angles and bonds) and its reactivity descriptors. The analysis of the molecular docking simulations showed that methylcytisine is coupled in the same active site of the NS5 enzyme methyltransferase DENV, very similar to the complexed ligand S-adenosyl-L-homocysteine. The intermolecular interactions found for the complex formed and the distance values of the enzyme residues, indicate that methylcytisine has potential application as a new inhibitor of the dengue virus, however it has a high possibility of interaction with human neuronal acetylcholine receptors.


2015 ◽  
Author(s):  
Manik Ghosh ◽  
Kamal Kant ◽  
Anoop Kumar ◽  
Padma Behera ◽  
Naresh Rangra ◽  
...  

2020 ◽  
Author(s):  
Rafael Espiritu

<p>Cholesterol-dependent cytolysins (CDCs) are proteinaceous toxins secreted as monomers by some Gram-positive and Gram-negative bacteria that contribute to their pathogenicity. These toxins bind to either cholesterol or human CD59, leading to massive structural changes, toxin oligomerization, formation of very large pores, and ultimately cell death, making these proteins promising targets for inhibition. Myricetin, and its related flavonoids, have been previously identified as a candidate small molecule inhibitor of specific CDCs such as listeriolysin O (LLO) and suilysin (SLY), interfering with their oligomerization. In this work, molecular docking was performed to assess the interaction of myricetin with other CDCs whose crystal structures are already known. Results indicated that although myricetin bound to the hitherto identified cavity in domain 4 (D4), much more efficient and stable binding was obtained in sites along the interfacial regions of domains 1 – 3 (D1 – D3). This was common among the tested CDCs, which was primarily due to much more extensive stabilizing intermolecular interactions, as indicated by post-docking analysis. Specifically, myricetin bound to (1) the interface of the three domains in anthrolysin O (ALO), perfringolysin O (PFO), pneumolysin (PLY), SLY, and vaginolysin (VLY), (2) at/near the D1/D3 interface in LLO and streptolysin O (SLO), and (3) along the D2/D3 interface in intermedilysin (ILY). These findings provide theoretical basis on the possibility of using myricetin and its related compounds as a broad-spectrum inhibitor of CDCs to potentially address the diseases associated with these pathogens.</p>


2019 ◽  
Vol 15 (6) ◽  
pp. 659-675
Author(s):  
Mohamed F. Zayed ◽  
Sabrin R.M. Ibrahim ◽  
EL-Sayed E. Habib ◽  
Memy H. Hassan ◽  
Sahar Ahmed ◽  
...  

Background: Quinazolines and quinazolinones derivatives are well known for their important range of therapeutic activities. Objective: The study aims to carry out the synthesis of some derivatives of substituted fluoroquinazolinones based on structure-based design and evaluation of their antibacterial, antifungal, and anti-biofilm activities. Methods: Compounds were chemically synthesized by conventional methods. Structures were established on the basis of spectral and elemental analyses. The antimicrobial potential was tested against various microorganisms using the agar disc-diffusion method. MIC and MBC as well as anti-biofilm activity for the highly active compounds were assessed. Moreover, the computational studies were performed using Auto dock free software package (version 4.0) to explain the predicted mode of binding. Results: All derivatives (5-8), (10a-g), and (A-H) were biologically tested and showed significant antimicrobial activity comparable to the reference compounds. Compounds 10b, 10c, and 10d had a good MIC and MBC against Gram-positive bacteria, whereas 10b and 10d showed significant MIC and MBC against Gram-negative bacteria. However, compounds E and F exhibited good MIC and MBC against fungi. Compound 10c and 8 exhibited significant anti-biofilm activity towards S. aureus and M. luteus. Molecular docking study revealed a strong binding of these derivatives with their receptor-site and detected their predicted mode of binding. Conclusion: The synthesized derivatives showed promising antibacterial, antifungal, and antibiofilm activities. Modeling study explained their binding mode and showed strong binding affinity with their receptor-site. The highly active compounds 5 and 10c could be subjected to future optimization and investigation to be effective antimicrobial agents.


2020 ◽  
Vol 16 (7) ◽  
pp. 892-902 ◽  
Author(s):  
Aida Iraji ◽  
Mahsima Khoshneviszadeh ◽  
Pegah Bakhshizadeh ◽  
Najmeh Edraki ◽  
Mehdi Khoshneviszadeh

Background: Melanogenesis is a process of melanin synthesis, which is a primary response for the pigmentation of human skin. Tyrosinase is a key enzyme, which catalyzes a ratelimiting step of the melanin formation. Natural products have shown potent inhibitors, but some of these possess toxicity. Numerous synthetic inhibitors have been developed in recent years may lead to the potent anti– tyrosinase agents. Objective: A number of 4-hydroxy-N'-methylenebenzohydrazide analogues with related structure to chalcone and tyrosine were constructed with various substituents at the benzyl ring of the molecule and evaluate as a tyrosinase inhibitor. In addition, computational analysis and metal chelating potential have been evaluated. Methods: Design and synthesized compounds were evaluated for activity against mushroom tyrosinase. The metal chelating capacity of the potent compound was examined using the mole ratio method. Molecular docking of the synthesized compounds was carried out into the tyrosine active site. Results: Novel 4-hydroxy-N'-methylenebenzohydrazide derivatives were synthesized. The two compounds 4c and 4g showed an IC50 near the positive control, led to a drastic inhibition of tyrosinase. Confirming in vitro results were performed via the molecular docking analysis demonstrating hydrogen bound interactions of potent compounds with histatidine-Cu+2 residues with in the active site. Kinetic study of compound 4g showed competitive inhibition towards tyrosinase. Metal chelating assay indicates the mole fraction of 1:2 stoichiometry of the 4g-Cu2+ complex. Conclusion: The findings in the present study demonstrate that 4-Hydroxy-N'- methylenebenzohydrazide scaffold could be regarded as a bioactive core inhibitor of tyrosinase and can be used as an inspiration for further studies in this area.


Sign in / Sign up

Export Citation Format

Share Document