Comparative docking studies to understand the binding affinity of nicotine with soluble ACE2 (sACE2)-SARS-CoV-2 complex over sACE2.
ABSTRACT: The study aimed to validate the proficiency of nicotine binding with the soluble angiotensin-converting enzyme II receptor (sACE2) with or without SARS-CoV-2 in the context of its binding affinity. Modelled human sACE2 and the spike (S1) protein of Indian SARS-CoV-2 (INS1) docked with each other. On the other hand, nicotine docked with sACE2 in the presence or absence of SARS-CoV-2. Nicotine established a stable interaction with negatively charged Asp368 of sACE2, which in turn binds with amino acids like Thr362, Lys363, Thr365, Thr371, and Ala372. In the presence of nicotine, INS1 and sACE2 showed a reduced binding affinity score of -12.6 kcal/mol (Vs -15.7 kcal/mol without nicotine), and a lowered interface area of 1933.6 Å2 (Vs 2057.3Å2 without nicotine). The neuronal nicotinic acetylcholine receptor (nN-AChR) and angiotensin-converting enzyme 2 (ACE2) receptor showed 19.85% sequence identity among themselves. Following these receptors possessed conserved Trp302 and Cys344 amino acids between them for nicotine binding. However, nicotine showed a higher binding affinity score of -6.33 kcal/mol for the sACE2-INS1 complex than the sACE2 alone with -5.24 kcal/mol. A lowered inhibitory constant value of 22.95?M recorded while nicotine interacted with the sACE2-INS1 complex over the sACE2 alone with 151.69 ?M. In summary, nicotine showed a profound binding affinity for the sACE2-INS1 complex than the sACE2 alone paving for the clinical trials to validate its therapeutic efficacy as a bitter compound against the SARS-CoV-2 virulence.
Project description:The current COVID-19 pandemic is caused by SARS CoV-2. To date, ?463,000 people died worldwide due to this disease. Several attempts have been taken in search of effective drugs to control the spread of SARS CoV-2 infection. The main protease (Mpro) from SARS CoV-2 plays a vital role in viral replication and thus serves as an important drug target. This Mpro shares a high degree of sequence similarity (>96%) with the same protease from SARS CoV-1 and MERS. It was already reported that Broussonetia papyrifera polyphenols efficiently inhibit the catalytic activity of SARS CoV-1 and MERS Mpro. But whether these polyphenols exhibit any inhibitory effect on SARS CoV-2 Mpro is far from clear. To understand this fact, here we have adopted computational approaches. Polyphenols having proper drug-likeness properties and two repurposed drugs (lopinavir and darunavir; having binding affinity -7.3 to -7.4?kcal/mol) were docked against SARS CoV-2 Mpro to study their binding properties. Only six polyphenols (broussochalcone A, papyriflavonol A, 3'-(3-methylbut-2-enyl)-3',4',7-trihydroxyflavane, broussoflavan A, kazinol F and kazinol J) had interaction with both the catalytic residues (His41 and Cys145) of Mpro and exhibited good binding affinity (-7.6 to -8.2?kcal/mol). Molecular dynamic simulations (100?ns) revealed that all Mpro-polyphenol complexes are more stable, conformationally less fluctuated; slightly less compact and marginally expanded than Mpro-darunavir/lopinavir complex. Even the number of intermolecular H-bond and MM-GBSA analysis suggested that these six polyphenols are more potent Mpro inhibitors than the two repurposed drugs (lopinavir and darunavir) and may serve as promising anti-COVID-19 drugs. Communicated by Ramaswamy H. Sarma.
Project description:Recent outbreak of COVID-19 pandemic caused by severe acute respiratory syndrome-Coronavirus-2 (SARS-CoV-2) has raised serious global concern for public health. The viral main 3-chymotrypsin-like cysteine protease (Mpro), known to control coronavirus replication and essential for viral life cycle, has been established as an essential drug discovery target for SARS-CoV-2. Herein, we employed computationally screening of Druglib database containing FDA approved drugs against active pocket of SARS-CoV-2 Mpro using MTiopen screen web server, yields a total of 1051 FDA approved drugs with docking energy >-7?kcal/mol. The top 10 screened potential compounds against SARS-CoV-2 Mpro were then studied by re-docking, binding affinity, intermolecular interaction, and complex stability via 100?ns all atoms molecular dynamics (MD) simulation followed by post-simulation analysis, including end point binding free energy, essential dynamics, and residual correlation analysis against native crystal structure ligand N3 inhibitor. Based on comparative molecular simulation and interaction profiling of the screened drugs with SARS-CoV-2 Mpro revealed R428 (-10.5?kcal/mol), Teniposide (-9.8?kcal/mol), VS-5584 (-9.4?kcal/mol), and Setileuton (-8.5?kcal/mol) with stronger stability and affinity than other drugs and N3 inhibitor; and hence, these drugs are advocated for further validation using in vitro enzyme inhibition and in vivo studies against SARS-CoV-2 infection. Communicated by Ramaswamy H. Sarma.
Project description:Ivermectin (IVM) is a broad-spectrum antiparasitic agent, having inhibitory potential against wide range of viral infections. It has also been found to hamper SARS-CoV-2 replication in vitro, and its precise mechanism of action against SARS-CoV-2 is yet to be understood. IVM is known to interact with host importin (IMP)? directly and averts interaction with IMP?1, leading to the prevention of nuclear localization signal (NLS) recognition. Therefore, the current study seeks to employ molecular docking, molecular mechanics generalized Born surface area (MM-GBSA) analysis and molecular dynamics simulation studies for decrypting the binding mode, key interacting residues as well as mechanistic insights on IVM interaction with 15 potential drug targets associated with COVID-19 as well as IMP?. Among all COVID-19 targets, the non-structural protein 9 (Nsp9) exhibited the strongest affinity to IVM showing -5.30?kcal/mol and -84.85?kcal/mol binding energies estimated by AutoDock Vina and MM-GBSA, respectively. However, moderate affinity was accounted for IMP? amounting -6.9?kcal/mol and -66.04?kcal/mol. Stability of the protein-ligand complexes of Nsp9-IVM and IMP?-IVM was ascertained by 100?ns trajectory of all-atom molecular dynamics simulation. Structural conformation of protein in complex with docked IVM exhibited stable root mean square deviation while root mean square fluctuations were also found to be consistent. In silico exploration of the potential targets and their interaction profile with IVM can assist experimental studies as well as designing of COVID-19 drugs.
Project description:COVID-19 (Coronavirus disease 2019) is a transmissible disease initiated and propagated through a new virus strain SARS-CoV-2 (Severe Acute Respiratory Syndrome Coronavirus-2) since 31st December 2019 in Wuhan city of China and the infection has outspread globally influencing millions of people. Here, an attempt was made to recognize natural phytochemicals from medicinal plants, in order to reutilize them against COVID-19 by the virtue of molecular docking and molecular dynamics (MD) simulation study. Molecular docking study showed six probable inhibitors against SARS-CoV-2 Mpro (Main protease), two from Withania somnifera (Ashwagandha) (Withanoside V [10.32?kcal/mol] and Somniferine [9.62?kcal/mol]), one from Tinospora cordifolia (Giloy) (Tinocordiside [8.10?kcal/mol]) and three from Ocimum sanctum (Tulsi) (Vicenin [8.97?kcal/mol], Isorientin 4'-O-glucoside 2?-O-p-hydroxybenzoagte [8.55?kcal/mol] and Ursolic acid [8.52?kcal/mol]). ADMET profile prediction showed that the best docked phytochemicals from present work were safe and possesses drug-like properties. Further MD simulation study was performed to assess the constancy of docked complexes and found stable. Hence from present study it could be suggested that active phytochemicals from medicinal plants could potentially inhibit Mpro of SARS-CoV-2 and further equip the management strategy against COVID-19-a global contagion. Highlights Holistic approach of Ayurvedic medicinal plants to avenge against COVID-19 pandemic. Active phytoconstituents of Ayurvedic medicinal plants Withania somnifera (Ashwagandha), Tinospora cordifolia (Giloy) and Ocimum sanctum (Tulsi) predicted to significantly hinder main protease (Mpro or 3Clpro) of SARS-CoV-2. Through molecular docking and molecular dynamic simulation study, Withanoside V, Somniferine, Tinocordiside, Vicenin, Ursolic acid and Isorientin 4'-O-glucoside 2?-O-p-hydroxybenzoagte were anticipated to impede the activity of SARS-CoV-2 Mpro. Drug-likeness and ADMET profile prediction of best docked compounds from present study were predicted to be safe, drug-like compounds with no toxicity. Communicated by Ramaswamy H. Sarma.
Project description:The COVID-19 pandemic, caused by SARS CoV-2, is responsible for millions of death worldwide. No approved/proper therapeutics is currently available which can effectively combat this outbreak. Several attempts have been undertaken in the search of effective drugs to control the spread of SARS CoV-2 infection. The main protease (Mpro), key component for the cleavage of the viral polyprotein, is considered to be one of the important drug targets for treating COVID-19. Various phytochemicals, including polyphenols and alkaloids, have been proposed as potent inhibitors of Mpro. The alkaloids from leaf extracts of Justicia adhatoda have also been reported to possess anti-viral activity. But whether these alkaloids exhibit any inhibitory effect on SARS CoV-2 Mpro is far from clear. To explore this in detail, we have adopted computational approaches. Justicia adhatoda alkaloids possessing proper drug-likeness properties and two anti-HIV drugs (lopinavir and darunavir; having binding affinity -7.3 to -7.4 kcal/mol) were docked against SARS CoV-2 Mpro to study their binding properties. Only one alkaloid (anisotine) had interaction with both the catalytic residues (His41 and Cys145) of Mpro and exhibited good binding affinity (-7.9 kcal/mol). Molecular dynamic simulations (100 ns) revealed that Mpro-anisotine complex is more stable, conformationally less fluctuated; slightly less compact and marginally expanded than Mpro-darunavir/lopinavir complex. Even the number of intermolecular H-bonds and MM-GBSA analysis suggested that anisotine is a more potent Mpro inhibitor than the two previously recommended antiviral drugs (lopinavir and darunavir) and may evolve as a promising anti-COVID-19 drug if proven in animal experiments and on patients.
Project description:The recent pandemic outbreak of SARS-CoV-2 associated with lethal atypical pneumonia COVID-19 is an urgent public health issue with an increasing rate of mortality and morbidity. Currently, there are no vaccines or therapeutics available for COVID-19 that demands an urgent search for a new drug to combat the pandemic of COVID-19. Lipid membrane alternation efficiency of small antimicrobial lipopeptides makes them able to block the viral membrane fusion to the host cell. Lipopeptides could serve as potential antiviral agents by interacting or competing with viral fusion proteins. Here, we screened seven different lipopeptides (tsushimycin, daptomycin, surfactin, bacillomycin, iturin, srfTE, LPD-12) and docked individually against spike (S)-glycoprotein of SARS-CoV-2. Based on the maximum docked score and minimum atomic contact energy, LPD-12 (-1137.38 kcal) is chosen appropriate molecule for proper binding with the S glycoprotein of SARS-CoV-2 and thus significantly interrupt its affinity of binding with angiotensin-converting enzyme-2 (ACE2), the only receptor molecule facilitates in disease development. Results confirm a strong binding affinity of LPD-12 with ACE2 with a binding free energy of -1621.62 kcal which can also prevent the binding of S-protein, reciprocally. Thus it can be concluded that LPD-12 may act as a potential therapeutic drug by reducing the entry of SARS-CoV-2 to the human cells via ACE2 receptor and related infections.
Project description:The novel coronavirus, COVID-19, caused by SARS-CoV-2, is a global health pandemic that started in December 2019. The effective drug target among coronaviruses is the main protease Mpro, because of its essential role in processing the polyproteins that are translated from the viral RNA. In this study, the bioactivity of some selected heterocyclic drugs named Favipiravir (1), Amodiaquine (2), 2'-Fluoro-2'-deoxycytidine (3), and Ribavirin (4) was evaluated as inhibitors and nucleotide analogues for COVID-19 using computational modeling strategies. The density functional theory (DFT) calculations were performed to estimate the thermal parameters, dipole moment, polarizability, and molecular electrostatic potential of the present drugs; additionally, Mulliken atomic charges of the drugs as well as the chemical reactivity descriptors were investigated. The nominated drugs were docked on SARS-CoV-2 main protease (PDB: 6LU7) to evaluate the binding affinity of these drugs. Besides, the computations data of DFT the docking simulation studies was predicted that the Amodiaquine (2) has the least binding energy (-7.77 Kcal/mol) and might serve as a good inhibitor to SARS-CoV-2 comparable with the approved medicines, hydroxychloroquine, and remdesivir which have binding affinity -6.06 and -4.96 Kcal/mol, respectively. The high binding affinity of 2 was attributed to the presence of three hydrogen bonds along with different hydrophobic interactions between the drug and the critical amino acids residues of the receptor. Finally, the estimated molecular electrostatic potential results by DFT were used to illustrate the molecular docking findings. The DFT calculations showed that drug 2 has the highest of lying HOMO, electrophilicity index, basicity, and dipole moment. All these parameters could share with different extent to significantly affect the binding affinity of these drugs with the active protein sites.
Project description:An outbreak of Coronavirus disease 2019 (COVID-19) caused by SARS-CoV-2 has been recognized as a global health concern. Since, no specific antiviral drug is proven effective for treatment against COVID-19, identification of new therapeutics is an urgent need. In this study, flavonoid compounds were analyzed for its inhibitory potential against important protein targets of SARS-CoV-2 using computational approaches. Virtual docking was performed for screening of flavonoid compounds retrieved from PubChem against the main protease of SARS-CoV-2 using COVID-19 docking server. The cut off of dock score was set to >-9kcal/mol and screened compounds were individually docked against main protease, RNA-dependent RNA polymerase, and spike proteins using AutoDock 4.1 software. Finally, lead flavonoid compounds were subjected to ADMET analysis. A total of 458 flavonoid compounds were virtually screened against main protease target and 36 compounds were selected based on the interaction energy value >-9kcal/mol. Furthermore, these compounds were individually docked against protein targets and top 10 lead compounds were identified. Among the lead compounds, agathisflavone showed highest binding energy value of -8.4 kcal/mol against main protease, Albireodelphin showed highest dock score of -9.8 kcal/mol and -11.2 kcal/mol against RdRp, and spike proteins, respectively. Based on the high dock score and ADMET properties, top 5 lead molecules such as Albireodelphin, Apigenin 7-(6''-malonylglucoside), Cyanidin-3-(p-coumaroyl)-rutinoside-5-glucoside, Delphinidin 3-O-beta-D-glucoside 5-O-(6-coumaroyl-beta-D-glucoside) and (-)-Maackiain-3-O-glucosyl-6''-O-malonate were identified as potent inhibitors against main protease, RdRp, and spike protein targets of SARS-CoV-2. These all compounds are having non-carcinogenic and non-mutagenic properties.This study finding suggests that the screened compounds include Albireodelphin, Apigenin 7-(6''-malonylglucoside), Cyanidin-3-(p-coumaroyl)-rutinoside-5-glucoside, Delphinidin 3-O-beta-D-glucoside 5-O-(6-coumaroyl-beta-D-glucoside) and (-)-Maackiain-3-O-glucosyl-6''-O-malonate could be the potent inhibitors of SARS-CoV-2 targets.
Project description:The 2019-novel coronavirus (nCoV) has caused a global health crisis by causing coronavirus disease-19 (COVID-19) pandemic in the human population. The unavailability of specific vaccines and anti-viral drug for nCoV, science demands sincere efforts in the field of drug design and discovery for COVID-19. The novel coronavirus main protease (SARS-CoV-2 Mpro) play a crucial role during the disease propagation, and hence SARS-CoV-2 Mpro represents as a drug target for the drug discovery. Herein, we have applied bioinformatics approach for screening of chemical compounds from Indian spices as potent inhibitors of SARS-CoV-2 main protease (PDBID: 6Y84). The structure files of Indian spices chemical compounds were taken from PubChem database or Zinc database and screened by molecular docking, by using AutoDock-4.2, MGLTools-1.5.6, Raccoon virtual screening tools. Top 04 hits based on their highest binding affinity were analyzed. Carnosol exhibited highest binding affinity -8.2?Kcal/mol and strong and stable interactions with the amino acid residues present on the active site of SARS-CoV-2 Mpro. Arjunglucoside-I (-7.88?Kcal/mol) and Rosmanol (-7.99?Kcal/mol) also showed a strong and stable binding affinity with favourable ADME properties. These compounds on MD simulations for 50ns shows strong hydrogen-bonding interactions with the protein active site and remains stable inside the active site. Our virtual screening results suggest that these small chemical molecules can be used as potential inhibitors against SARS-CoV-2 Mpro and may have an anti-viral effect on nCoV. However, further validation and investigation of these inhibitors against SARS-CoV-2 main protease are needed to claim their candidacy for clinical trials.
Project description:Introduction:The extreme health and economic problems in the world due to the SARS-CoV-2 infection have led to an urgent need to identify potential drug targets for treating coronavirus disease 2019 (COVID-19). The present state-of-the-art tool-based screening was targeted to identify drug targets among clinically approved drugs by uncovering SARS-CoV-2 helicase inhibitors through molecular docking analysis. Material and methods:Helicase is a vital viral replication enzyme, which unwinds nucleic acids and separates the double-stranded nucleic acids into single-stranded nucleic acids. Hence, the SARS-CoV-2 helicase protein 3D structure was predicted, validated, and used to screen the druggable targets among clinically approved drugs such as protease inhibitor, nucleoside reverse transcriptase inhibitor, and non-nucleoside reverse transcriptase inhibitors, used to treat HIV infection using molecular docking analysis. Results:Interaction with SARS-CoV-2 helicase, approved drugs, vapreotide (affinity: -12.88; S score: -9.84 kcal/mol), and atazanavir (affinity: -11.28; S score: -9.32 kcal/mol), approved drugs for treating AIDS-related diarrhoea and HIV infection, respectively, are observed with significantly low binding affinity and MOE score or binding free energy. The functional binding pockets of the clinically approved drugs on SARS-CoV-2 helicase protein molecule suggest that vapreotide and atazanavir may interrupt the activities of the SARS-CoV-2 helicase. Conclusions:The study suggests that vapreotide may be a choice of drug for wet lab studies to inhibit the infection of SARS-CoV-2.