Luteolin and abyssinone II as potential inhibitors of SARS-CoV-2: an in silico molecular modeling approach in battling the COVID-19 outbreak

Abstract Background At present, the entire world is in a war against COVID-19 pandemic which has gradually led us toward a more compromised “new normal” life. SARS-CoV-2, the pathogenic microorganism liable for the recent COVID-19 outbreak, is extremely contagious in nature resulting in an unusual number of infections and death globally. The lack of clinically proven therapeutic intervention for COVID-19 has dragged the world’s healthcare system into the biggest challenge. Therefore, development of an efficient treatment scheme is now in great demand. Screening of different biologically active plant-based natural compounds could be a useful strategy for combating this pandemic. In the present research, a collection of 43 flavonoids of 7 different classes with previously recorded antiviral activity was evaluated via computational and bioinformatics tools for their impeding capacity against SARS-CoV-2. In silico drug likeness, pharmacophore and Absorption, Distribution, Metabolism, Excretion and Toxicity (ADMET) profile analysis of the finest ligands were carried out using DataWarrior, DruLiTo and admetSAR programs, respectively. Molecular docking was executed by AutoDock Vina, while molecular dynamics simulation of the target protein–ligand bound complexes was done using nanoscalable molecular dynamics and visual molecular dynamics software package. Finally, the molecular target analysis of the selected ligands within Homo sapiens was conducted with SwissTargetPredcition web server. Results Out of the forty-three flavonoids, luteolin and abyssinone II were found to develop successful docked complex within the binding sites of target proteins in terms of lowest binding free energy and inhibition constant. The root mean square deviation and root mean square fluctuation values of the docked complex displayed stable interaction and efficient binding between the ligands and target proteins. Both of the flavonoids were found to be safe for human use and possessed good drug likeness properties and target accuracy. Conclusions Conclusively, the current study proposes that luteolin and abyssinone II might act as potential therapeutic candidates for SARS-CoV-2 infection. In vivo and in vitro experiments, however, should be taken under consideration to determine the efficiency and to demonstrate the mechanism of action.

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Identification of Potential SARS-CoV-2 Main Protease and Spike Protein Inhibitors from the Genus Aloe: An In Silico Study for Drug Development

Molecules ◽

10.3390/molecules26061767 ◽

2021 ◽

Vol 26 (6) ◽

pp. 1767

Author(s):

Mohamed E. Abouelela ◽

Hamdy K. Assaf ◽

Reda A. Abdelhamid ◽

Ehab S. Elkhyat ◽

Ahmed M. Sayed ◽

...

Keyword(s):

Molecular Dynamics ◽

Molecular Dynamics Simulation ◽

Drug Development ◽

Root Mean Square ◽

In Silico ◽

Dynamics Simulation ◽

Spike Protein ◽

Energy Calculation ◽

Mean Square ◽

Main Protease

Severe acute respiratory syndrome coronavirus (SARS-CoV-2) disease is a global rapidly spreading virus showing very high rates of complications and mortality. Till now, there is no effective specific treatment for the disease. Aloe is a rich source of isolated phytoconstituents that have an enormous range of biological activities. Since there are no available experimental techniques to examine these compounds for antiviral activity against SARS-CoV-2, we employed an in silico approach involving molecular docking, dynamics simulation, and binding free energy calculation using SARS-CoV-2 essential proteins as main protease and spike protein to identify lead compounds from Aloe that may help in novel drug discovery. Results retrieved from docking and molecular dynamics simulation suggested a number of promising inhibitors from Aloe. Root mean square deviation (RMSD) and root mean square fluctuation (RMSF) calculations indicated that compounds 132, 134, and 159 were the best scoring compounds against main protease, while compounds 115, 120, and 131 were the best scoring ones against spike glycoprotein. Compounds 120 and 131 were able to achieve significant stability and binding free energies during molecular dynamics simulation. In addition, the highest scoring compounds were investigated for their pharmacokinetic properties and drug-likeness. The Aloe compounds are promising active phytoconstituents for drug development for SARS-CoV-2.

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Identification of Phosphatidylinositol 3-kinase δ (PI3Kδ) Inhibitor: Pharmacophore-based Virtual Screening and Molecular Dynamics Simulation

Indonesian Journal of Chemistry ◽

10.22146/ijc.47327 ◽

2020 ◽

Vol 20 (5) ◽

pp. 1070

Author(s):

Muhammad Arba ◽

Malindo Sufriadin ◽

Daryono Hadi Tjahjono

Keyword(s):

Molecular Dynamics ◽

Root Mean Square ◽

Conformational Changes ◽

Binding Free Energy ◽

Pharmacophore Model ◽

Dynamics Simulation ◽

Mean Square ◽

Phosphatidylinositol 3 Kinase ◽

Pharmacophore Modelling ◽

Phosphatidylinositol 3

Phosphatidylinositol 3-kinase δ (PI3Kδ) is a validated drug target for the treatment of cancer. The present study aims to search for new inhibitors of PI3Kδ by employing pharmacophore modelling using LigandScout Advanced 4.3 software. The three hydrogen bond acceptors and two hydrophobic features were proposed as a pharmacophore model using LASW1976 structure. The model was then validated using the Area Under Curve (AUC) of Receiver Operating Characteristic (ROC) and GH score. It was used to screen new molecules in the ZINC database, which resulted in 599 hits. All 599 hits were then docked into PI3Kδ protein, and five best hits were submitted to 50 ns molecular dynamics simulations. Each hit complexed with PI3Kδ underwent minor conformational changes as indicated by the values of Root Mean Square Deviation (RMSD) and Root Mean Square Fluctuation (RMSF). Furthermore, prediction of the binding free energy using Molecular Mechanics-Poisson Boltzmann Surface Area (MM-PBSA) method showed that five hits, i.e., Lig25/ZINC253496376, Lig682/ZINC98047241, Lig449/ZINC85878047, Lig554/ZINC253389510, and Lig199/ZINC12638303, had lower binding energy compared to LASW1976. This result indicated their potentials as new inhibitors of PI3Kδ.

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Effects of the Temperature and the pH on the Main Protease of SARS-CoV-2: A Molecular Dynamics Simulation Study

Biointerface Research in Applied Chemistry ◽

10.33263/briac126.72397248 ◽

2021 ◽

Vol 12 (6) ◽

pp. 7239-7248

Keyword(s):

Molecular Dynamics ◽

Molecular Dynamics Simulation ◽

Root Mean Square ◽

Dynamics Simulation ◽

Effect Of Temperature ◽

Water Molecules ◽

Mean Square ◽

Main Protease ◽

Decreasing Ph ◽

Increasing Temperature

The novel coronavirus, recognized as COVID-19, is the cause of an infection outbreak in December 2019. The effect of temperature and pH changes on the main protease of SARS-CoV-2 were investigated using all-atom molecular dynamics simulation. The obtained results from the root mean square deviation (RMSD) and root mean square fluctuations (RMSF) analyses showed that at a constant temperature of 25℃ and pH=5, the conformational change of the main protease is more significant than that of pH=6 and 7. Also, by increasing temperature from 25℃ to 55℃ at constant pH=7, a remarkable change in protein structure was observed. The radial probability of water molecules around the main protease was decreased by increasing temperature and decreasing pH. The weakening of the binding energy between the main protease and water molecules due to the increasing temperature and decreasing pH has reduced the number of hydrogen bonds between the main protease and water molecules. Finding conditions that alter the conformation of the main protease could be fundamental because this change could affect the virus’s functionality and its ability to impose illness.

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In vitro evaluation and molecular dynamics, DFT guided investigation of antimalarial activity of ethnomedicinally used Coptis teeta Wall

Combinatorial Chemistry & High Throughput Screening ◽

10.2174/1386207324666210118095503 ◽

2021 ◽

Vol 24 ◽

Author(s):

Ashis Kumar Goswami ◽

Hemanta Kumar Sharma ◽

Neelutpal Gogoi ◽

Ankita Kashyap ◽

Bhaskar Jyoti Gogoi

Keyword(s):

Molecular Dynamics ◽

In Silico ◽

Density Functional ◽

Antimalarial Activity ◽

In Silico Analysis ◽

Dynamics Simulation ◽

Discovery Studio ◽

North East ◽

Silico Analysis

Background: Malaria is caused by different species of Plasmodium; among which P. falciparum is the most severe. Coptis teeta is an ethnomedicinal plant of enormous importance for tribes of north east India. Objective: In this study, the anti malarial activity of the methanol extracts of Coptis teeta was evaluated in vitro and lead identification via in silico study. Method: On the basis of the in vitro results, in silico analysis by application of different modules of Discovery Studio 2018 was performed on multiple targets of P. falciparum taking into consideration some of the compounds reported from C. teeta. Results: The IC50 of the methanol extract of Coptis teeta 0.08 µg/ml in 3D7 strain and 0.7 µg/ml in Dd2 strain of P. falciparum. From the docking study, noroxyhydrastatine was observed to have better binding affinity in comparison to chloroquine. The binding of noroxyhydrastinine with dihydroorotate dehydrogenase was further validated by molecular dynamics simulation and was observed to be significantly stable in comparison to the co-crystal inhibitor. During simulations it was observed that noroxyhydrastinine retained the interactions, giving strong indications of its effectiveness against the P. falciparum proteins and stability in the binding pocket. From the Density-functional theory analysis, the band gap energy of noroxyhydrastinine was found to be 0.186 Ha indicating a favourable interaction. Conclusion: The in silico analysis as an addition to the in vitro results provide strong evidence of noroxyhydrastinine as an anti malarial agent.

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Molecular Dynamics Simulation of Barnase: Contribution of Noncovalent Intramolecular Interaction to Thermostability

Mathematical Problems in Engineering ◽

10.1155/2013/504183 ◽

2013 ◽

Vol 2013 ◽

pp. 1-12 ◽

Cited By ~ 1

Author(s):

Zhiguo Chen ◽

Yi Fu ◽

Wenbo Xu ◽

Ming Li

Keyword(s):

Molecular Dynamics ◽

Thermal Stability ◽

Molecular Dynamics Simulation ◽

Root Mean Square ◽

Clinical Medicine ◽

Intramolecular Interaction ◽

Salt Bridge ◽

Dynamics Simulation ◽

Mean Square ◽

Thermal Stability Of

Bacillus amyloliquefaciensribonuclease Barnase (RNase Ba) is a 12 kD (kilodalton) small extracellular ribonuclease. It has broad application prospects in agriculture, clinical medicine, pharmaceutical, and so forth. In this work, the thermal stability of Barnase has been studied using molecular dynamics simulation at different temperatures. The present study focuses on the contribution of noncovalent intramolecular interaction to protein stability and how they affect the thermal stability of the enzyme. Profiles of root mean square deviation and root mean square fluctuation identify thermostable and thermosensitive regions of Barnase. Analyses of trajectories in terms of secondary structure content, intramolecular hydrogen bonds and salt bridge interactions indicate distinct differences in different temperature simulations. In the simulations, Four three-member salt bridge networks (Asp8-Arg110-Asp12, Arg83-Asp75-Arg87, Lys66-Asp93-Arg69, and Asp54-Lys27-Glu73) have been identified as critical salt bridges for thermostability which are maintained stably at higher temperature enhancing stability of three hydrophobic cores. The study may help enlighten our knowledge of protein structural properties, noncovalent interactions which can stabilize secondary peptide structures or promote folding, and also help understand their actions better. Such an understanding is required for designing efficient enzymes with characteristics for particular applications at desired working temperatures.

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Use of multiple picosecond high-mass molecular dynamics simulations to predict crystallographic B-factors of folded globular proteins

10.1101/052126 ◽

2016 ◽

Author(s):

Yuan-Ping Pang

Keyword(s):

Molecular Dynamics ◽

Molecular Dynamics Simulation ◽

Molecular Dynamics Simulations ◽

Root Mean Square ◽

A Priori ◽

Model Systems ◽

Dynamics Simulation ◽

High Mass ◽

Mean Square ◽

Dynamics Simulations

ABSTRACTPredicting crystallographic B-factors of a protein from a conventional molecular dynamics simulation is challenging in part because the B-factors calculated through sampling the atomic positional fluctuations in a picosecond molecular dynamics simulation are unreliable and the sampling of a longer simulation yields overly large root mean square deviations between calculated and experimental B-factors. This article reports improved B-factor prediction achieved by sampling the atomic positional fluctuations in multiple picosecond molecular dynamics simulations that use uniformly increased atomic masses by 100-fold to increase time resolution. Using the third immunoglobulin-binding domain of protein G, bovine pancreatic trypsin inhibitor, ubiquitin, and lysozyme as model systems, the B-factor root mean square deviations (mean ± standard error) of these proteins were 3.1 ± 0.2–9 ± 1 Å2for Cα and 7.3 ± 0.9–9.6 ± 0.2 Å2for Cγ, when the sampling was done, for each of these proteins, over 20 distinct, independent, and 50-picosecond high-mass molecular dynamics simulations using AMBER forcefield FF12MC or FF14SB. These results suggest that sampling the atomic positional fluctuations in multiple picosecond high-mass molecular dynamics simulations may be conducive toa prioriprediction of crystallographic B-factors of a folded globular protein.

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Mollusc-Derived Brominated Indoles for the Selective Inhibition of Cyclooxygenase: A Computational Expedition

Molecules ◽

10.3390/molecules26216538 ◽

2021 ◽

Vol 26 (21) ◽

pp. 6538

Author(s):

Md. Mominur Rahman ◽

Md. Junaid ◽

S. M. Zahid Hosen ◽

Mohammad Mostafa ◽

Lei Liu ◽

...

Keyword(s):

Molecular Dynamics ◽

Molecular Docking ◽

Molecular Dynamics Simulation ◽

Surface Area ◽

Root Mean Square ◽

Selective Inhibition ◽

Dynamics Simulation ◽

Solvent Accessible Surface Area ◽

Mean Square ◽

Cox 1

Inflammation plays an important role in different chronic diseases. Brominated indoles derived from the Australian marine mollusk Dicathais orbita (D. orbita) are of interest for their anti-inflammatory properties. This study evaluates the binding mechanism and potentiality of several brominated indoles (tyrindoxyl sulfate, tyrindoleninone, 6-bromoisatin, and 6,6′-dibromoindirubin) against inflammatory mediators cyclooxygenases-1/2 (COX-1/2) using molecular docking, followed by molecular dynamics simulation, along with physicochemical, drug-likeness, pharmacokinetic (pk), and toxicokinetic (tk) properties. Molecular docking identified that these indole compounds are anchored, with the main amino acid residues, positioned in the binding pocket of the COX-1/2, required for selective inhibition. Moreover, the molecular dynamics simulation based on root mean square deviation (RMSD), radius of gyration (Rg), solvent accessible surface area (SASA), and root mean square fluctuation (RMSF) analyses showed that these natural brominated molecules transit rapidly to a progressive constant configuration during binding with COX-1/2 and seem to accomplish a consistent dynamic behavior by maintaining conformational stability and compactness. The results were comparable to the Food and Drug Administration (FDA)-approved selective COX inhibitor, aspirin. Furthermore, the free energy of binding for the compounds assessed by molecular mechanics–Poisson–Boltzmann surface area (MM–PBSA) confirmed the binding capacity of indoles towards COX-1/2, with suitable binding energy values except for the polar precursor tyrindoxyl sulfate (with COX-1). The physicochemical and drug-likeness analysis showed zero violations of Lipinski’s rule, and the compounds are predicted to have excellent pharmacokinetic profiles. These indoles are projected to be non-mutagenic and free from hepatotoxicity, with no inhibition of human ether-a-go–go gene (hERG) I inhibitors, and the oral acute toxicity LD50 in rats is predicted to be similar or lower than aspirin. Overall, this work has identified a plausible mechanism for selective COX inhibition by natural marine indoles as potential therapeutic candidates for the mitigation of inflammation.

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In Silico and In Vitro Evaluation of the Antimicrobial Potential of Bacillus cereus Isolated from Apis dorsata Gut against Neisseria gonorrhoeae

Antibiotics ◽

10.3390/antibiotics10111401 ◽

2021 ◽

Vol 10 (11) ◽

pp. 1401

Author(s):

Nurdjannah Jane Niode ◽

Aryani Adji ◽

Jimmy Rimbing ◽

Max Tulung ◽

Mohammed Alorabi ◽

...

Keyword(s):

Neisseria Gonorrhoeae ◽

Bacillus Cereus ◽

In Silico ◽

Pathogenic Bacteria ◽

Hydrophobic Interactions ◽

Binding Free Energy ◽

Dynamics Simulation ◽

Apis Dorsata ◽

Associated Bacteria

Antimicrobial resistance is a major public health and development concern on a global scale. The increasing resistance of the pathogenic bacteria Neisseria gonorrhoeae to antibiotics necessitates efforts to identify potential alternative antibiotics from nature, including insects, which are already recognized as a source of natural antibiotics by the scientific community. This study aimed to determine the potential of components of gut-associated bacteria isolated from Apis dorsata, an Asian giant honeybee, as an antibacterial against N. gonorrhoeae by in vitro and in silico methods as an initial process in the stage of new drug discovery. The identified gut-associated bacteria of A. dorsata included Acinetobacter indicus and Bacillus cereus with 100% identity to referenced bacteria from GenBank. Cell-free culture supernatants (CFCS) of B. cereus had a very strong antibacterial activity against N. gonorrhoeae in an in vitro antibacterial testing. Meanwhile, molecular docking revealed that antimicrobial lipopeptides from B. cereus (surfactin, fengycin, and iturin A) had a comparable value of binding-free energy (BFE) with the target protein receptor for N. gonorrhoeae, namely penicillin-binding protein (PBP) 1 and PBP2 when compared with the ceftriaxone, cefixime, and doxycycline. The molecular dynamics simulation (MDS) study revealed that the surfactin remains stable at the active site of PBP2 despite the alteration of the H-bond and hydrophobic interactions. According to this finding, surfactin has the greatest antibacterial potential against PBP2 of N. gonorrhoeae.

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Reappraisal of Trifluperidol against NSP-3 protein: Potential therapeutic for COVID-19

10.21203/rs.3.rs-52706/v1 ◽

2020 ◽

Author(s):

Ajita Pandey

Keyword(s):

Root Mean Square ◽

Dynamics Simulation ◽

Solvent Accessible Surface Area ◽

Radius Of Gyration ◽

Scoring Functions ◽

Mean Square ◽

Structural Protein ◽

Approved Drugs ◽

Fda Approved Drugs

Abstract Novel coronavirus disease 2019 (COVID-19) is a highly infectious disease that is caused by the recently discovered severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Because there are no specific vaccines or drugs for SARS-CoV-2, drug repurposing may be a promising approach. SARS-CoV-2 has a positive-sense RNA genome that encodes non-structural proteins (Nsps), which are essential for viral replication in the host cell. Non-structural protein 3 (Nsp3) is a multidomain protein and is the largest protein of the replicase complex. Nsp3 contains an ADP-ribose phosphatase (ADRP) domain, also called the macrodomain, which interferes with the host immune response. In the present study, we used computational regression methods to target the ADRP domain of Nsp3, using FDA-approved drugs. We virtually screened 2,892 FDA-approved drugs, using a combination of molecular docking and scoring functions. Saquinavir and trifluperidol were identified as potential leads and were further investigated using molecular dynamics simulation (MDS) to predict the stability and behavior of the ADRP-drug complexes. Analysis of root mean square deviation, root mean square fluctuation, radius of gyration, solvent accessible surface area and number of hydrogen bonds showed that the ADRP-trifluperidol complex is more stable than the ADRP-saquinavir complex. The screening and the MDS results suggest that trifluperidol is a novel inhibitor of the ADRP domain of Nsp3. Trifluperidol could, therefore, potentially be used to help control the spread of COVID-19, either alone or in combination with antiviral agents. Further in-vitro and in-vivo experiments are necessary to confirm our in silico results.

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Molecular Dynamics Study of Insulin Mutants

East European Journal of Physics ◽

10.26565/2312-4334-2021-2-15 ◽

2021 ◽

Keyword(s):

Molecular Dynamics ◽

Protein Structure ◽

Secondary Structure ◽

Root Mean Square ◽

Human Insulin ◽

Dynamics Simulation ◽

Solvent Accessible Surface Area ◽

Mean Square ◽

Wild Type ◽

Secondary Structure Content

Human insulin, a small protein hormone consisting of A-chain (21 residues) and B-chain (30 residues) linked by three disulfide bonds, is crucial for controlling the hyperglycemia in type I diabetes. In the present work molecular dynamics simulation (MD) with human insulin and its mutants was used to assess the influence of 10 point mutations (HisA8, ValA10, AspB10, GlnB17, AlaB17, GlnB18, AspB25, ThrB26, GluB27, AspB28), 6 double mutations (GluA13+GluB10, SerA13+GluB27, GluB1+GluB27, SerB2+AspB10, AspB9+GluB27, GluB16+GluB27) and one triple mutation (GluA15+AspA18+AspB3) in the protein sequence on the structure and dynamics of human insulin. A series of thermal unfolding MD simulations with wild type (WT) human insulin and its mutants was performed at 400 K with GROMACS software (version 5.1) using the CHARMM36m force field. The MD results have been analyzed in terms of the parameters characterizing both the global and local protein structure, such as the backbone root mean-square deviation, gyration radius, solvent accessible surface area, the root mean-square fluctuations and the secondary structure content. The MD simulation data showed that depending on time evolution of integral characteristics, the examined mutants can be tentatively divided into three groups: 1) the mutants HisA8, ValA10, AlaB17, AspB25, ThrB26, GluB27, GluA13+GluB10, GluB1+GluB27 and GluB16+GluB27, which exert stabilizing effect on the protein structure in comparison with wild type insulin; 2) the mutants GlnB17, AspB10, SerB2+AspB10 and GluA15+AspA18+AspB3 that did not significantly affect the dynamical properties of human insulin with a minimal stabilizing impact; 3) the mutants AspB28, AspB9+GluB27 and SerA13+GluB27, GlnB18, destabilizing the protein structure. Analysis of the secondary structure content provided evidence for the influence of AspB28, AspB9+GluB27 and SerA13+GluB27, GlnB18 on the insulin unfolding. Our MD results indicate that the replacement of superficial nonpolar residues in the insulin structure by hydrophilic ones gives rise to the increase in protein stability in comparison with the wild type protein.

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