scholarly journals A Study of 3CLpros as Promising Targets against SARS-CoV and SARS-CoV-2

2021 ◽  
Vol 9 (4) ◽  
pp. 756
Author(s):  
Seri Jo ◽  
Suwon Kim ◽  
Jahyun Yoo ◽  
Mi-Sun Kim ◽  
Dong Hae Shin
Keyword(s):  
Protein Function ◽  
Antiviral Agents ◽  
Drug Repurposing ◽  
Docking Study ◽  
Inhibitory Effect ◽  
Active Site Residues ◽  
In Silico Docking ◽  
Inhibitory Function ◽  
Phosphodiesterase Type 5 Inhibitor ◽  
Phosphodiesterase Type

The outbreak of coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), results in serious chaos all over the world. In addition to the available vaccines, the development of treatments to cure COVID-19 should be done quickly. One of the fastest strategies is to use a drug-repurposing approach. To provide COVID-19 patients with useful information about medicines currently being used in clinical trials, twenty-four compounds, including antiviral agents, were selected and assayed. These compounds were applied to verify the inhibitory activity for the protein function of 3CLpros (main proteases) of SARS-CoV and SARS-CoV-2. Among them, viral reverse-transcriptase inhibitors abacavir and tenofovir revealed a good inhibitory effect on both 3CLpros. Intriguingly, sildenafil, a cGMP-specific phosphodiesterase type 5 inhibitor also showed significant inhibitory function against them. The in silico docking study suggests that the active-site residues located in the S1 and S2 sites play key roles in the interactions with the inhibitors. The result indicates that 3CLpros are promising targets to cope with SAR-CoV-2 and its variants. The information can be helpful to design treatments to cure patients with COVID-19.

Determination of binding potential of HCV protease inhibitors against SARS-CoV-2 Papain-like protease with computational docking

2021 ◽  
Vol 18 ◽  
Author(s):  
Zihni Onur Çalışkaner
Keyword(s):  
Protease Inhibitors ◽  
Drug Repurposing ◽  
Docking Study ◽  
Binding Energies ◽  
Binding Potential ◽  
Computational Docking ◽  
In Silico Docking ◽  
Hcv Protease ◽  
Novel Coronavirus ◽  
Inhibitory Molecules

Background: SARS-CoV-2, a novel coronavirus that causes a pandemic respiratory disease, has recently emerged from China. Since it’s a life-threatening virus, investigation of curative medications along with protective vaccines still maintains its importance. Drug repurposing is a reasonable and immediate approach to combat SARS-CoV-2 infection by identifying inhibitory molecules from marketed drugs. PL protease (PLpro.) is one of the essential enzymes for the progression of SARS-CoV-2 replication and life cycle. Objective: We aimed to investigate the potential of 4 HCV protease inhibitors as probable repurposing drugs in Covid-19 treatment. Methods: In order to understand the possible binding affinity of HCV protease inhibitors, Boceprevir, Grazoprevir, Simeprevir, and Telaprevir, against to PLpro, we performed docking analysis in silico. Docking study was accomplished using AutoDock 4.2 software. Potential druggable pockets on PLpro were predicted by DoGSiteScorer tool in order to explore any overlapping with binding regions and these pockets. Results: This analysis demonstrated Boceprevir, Grazoprevir, Simeprevir and Telaprevir interacted by PLpro with binding energies (kcal/mol) of -4.97, -4.24, -6.98, -1.08, respectively. Asn109, one of the interacted residues with both Boceprevir and Simeprevir, is a neighbouring residue to catalytic Cys111. Additionally, Telaprevir notably interacted with catalytic His272 in the active site. Conclusion: Present study explains the binding efficiency and repurposing potential of certain HCV protease inhibitors against to SARS-CoV-2 PLpro enzyme. Docking sites and potential druggability of ligands were also crosschecked by the estimation of druggable pockets. Thereby our results can promote promising preliminary data for research on drug development in the fight of Covid-19.

1202: Long-Term Phosphodiesterase Type 5 Inhibitor Therapy Reduces Priapic Activity in Transgenic Sickle Cell Mice

2006 ◽  
Vol 175 (4S) ◽  
pp. 387-387 ◽  
Author(s):  
Trinity J. Bivalacqua ◽  
Hunter C. Champion ◽  
Warren Mason ◽  
Arthur L. Burnett
Keyword(s):  
Sickle Cell ◽  
Inhibitor Therapy ◽  
Phosphodiesterase Type 5 Inhibitor ◽  
Phosphodiesterase Type

The Antiviral and Antimalarial Drug Repurposing in Quest of Chemotherapeutics to Combat COVID-19 Utilizing Structure-Based Molecular Docking

2020 ◽  
Vol 23 ◽  
Author(s):  
Sisir Nandi ◽  
Mohit Kumar ◽  
Mridula Saxena ◽  
Anil Kumar Saxena
Keyword(s):  
Molecular Docking ◽  
In Silico ◽  
Drug Repurposing ◽  
Clinical Settings ◽  
The Novel ◽  
In Silico Docking ◽  
Biochemical Mechanisms ◽  
Novel Coronavirus ◽  
In Silico Molecular Docking

Background: The novel coronavirus disease (COVID-19) is caused by a new strain (SARS-CoV-2) erupted in 2019. Nowadays, it is a great threat that claims uncountable lives worldwide. There is no specific chemotherapeutics developed yet to combat COVID-19. Therefore, scientists have been devoted in the quest of the medicine that can cure COVID- 19. Objective: Existing antivirals such as ASC09/ritonavir, lopinavir/ritonavir with or without umifenovir in combination with antimalarial chloroquine or hydroxychloroquine have been repurposed to fight the current coronavirus epidemic. But exact biochemical mechanisms of these drugs towards COVID-19 have not been discovered to date. Method: In-silico molecular docking can predict the mode of binding to sort out the existing chemotherapeutics having a potential affinity towards inhibition of the COVID-19 target. An attempt has been made in the present work to carry out docking analyses of 34 drugs including antivirals and antimalarials to explain explicitly the mode of interactions of these ligands towards the COVID-19protease target. Results: 13 compounds having good binding affinity have been predicted towards protease binding inhibition of COVID-19. Conclusion: Our in silico docking results have been confirmed by current reports from clinical settings through the citation of suitable experimental in vitro data available in the published literature.

Development of Xanthine Based Inhibitors Targeting Phosphodiesterase 9A

2017 ◽  
Vol 14 (10) ◽  
pp. 1122-1137 ◽  
Author(s):  
Nivedita Singh ◽  
Parameswaran Saravanan ◽  
M.S. Thakur ◽  
Sanjukta Patra
Keyword(s):  
Free Energy ◽  
Active Site ◽  
Signal Transduction Pathway ◽  
Docking Study ◽  
Primary Objective ◽  
Cgmp Level ◽  
Active Site Residues ◽  
Aromatic Fragment ◽  
Docking Approach ◽  
Free Energy Of Binding

Background: Phosphodiesterases 9A (PDE9A) is one of the prominent regulating enzymes of the signal transduction pathway having highest catalytic affinity for second messenger, cGMP. When the cGMP level is lowered, an uncontrolled expression of PDE9A may lead to various neurodegenerative diseases. To regulate the catalytic activity of PDE9A, potent inhibitors are needed. Objective: The primary objective of the present study was to develop new xanthine based inhibitors targeting PDE9A. This study was an attempt to bring structural diversification in PDE9A inhibitor development because most of the existing inhibitors are constructed over pyrazolopyrimidinone scaffold. Methods: Manual designing and parallel molecular docking approach were used for the development of xanthine derivatives. In this study, N1, N3, N9 and C8 positions of xanthine scaffold were selected as substitution sites to design 200 new compounds. Reverse docking and pharmaceutical analyses were used for final validation of most promising compounds. Results: By keeping free energy of binding cut-off of -6.0 kcal/mol, 52 compounds were screened. The compounds with substitution at N1, N3 and C8 positions of xanthine showed good occupancy in PDE9A active site pocket with a significant interaction pattern. This was further validated by screening different factors such as free energy of binding, inhibition constant and interacting active site residues in the 5Å region. Substitution at C8 position with phenyl substituent determined the inhibition affinity of compounds towards PDE9A by establishing a strong hydrophobic - hydrophobic interaction. The alkyl chain at N1 position generated selectivity of compounds towards PDE9A. The aromatic fragment at N3 position increased the binding affinity of compounds. Thus, by comparative docking study, it was found that compound 39-42 formed selective interaction towards PDE9A over other members of the PDE superfamily. Conclusion: From the present study, N1, N3 and C8 positions of xanthine were concluded as the best sites for substitution for the generation of potent PDE9A inhibitors.

Hetero-Tricyclic Lead Scaffold as Novel PDE5A Inhibitor for Antihypertensive Activity: In Silico Docking Studies

2019 ◽  
Vol 15 (4) ◽  
pp. 318-333
Author(s):  
Dipak P. Mali ◽  
Neela M. Bhatia
Keyword(s):  
In Silico ◽  
Docking Study ◽  
Docking Studies ◽  
Antihypertensive Activity ◽  
In Silico Docking ◽  
Π Stacking ◽  
Π Stacking Interaction ◽  
Nitrogen Heteroatom ◽  
Inhibitory Potential ◽  
Vlife Mds

Objective:To screen the phytochemicals for phosphodiesterase 5A (PDE5A) inhibitory potential and identify lead scaffolds of antihypertensive phytochemicals using in silico docking studies.Methods:In this perspective, reported 269 antihypertensive phytochemicals were selected. Sildenafil, a PDE5A inhibitor was used as the standard. In silico docking study was carried out to screen and identify the inhibiting potential of the selected phytochemicals against PDE5A enzyme using vLife MDS 4.4 software.Results:Based on docking score, π-stacking, H-bond and ionic interactions, 237 out of 269 molecules were selected which have shown one or more interactions. Protein residue Gln817A was involved in H-boding whereas Val782A, Phe820A and Leu804A were involved in π-stacking interaction with ligand. The selected 237 phytochemicals were structurally diverse, therefore 82 out of 237 molecules with one or more tricycles were filtered out for further analysis. Amongst tricyclic molecules, 14 molecules containing nitrogen heteroatom were selected for lead scaffold identification which finally resulted in three different basic chemical backbones like pyridoindole, tetrahydro-pyridonaphthyridine and dihydro-pyridoquinazoline as lead scaffolds.Conclusion:In silico docking studies revealed that nitrogen-containing tetrahydro-pyridonaphthyridine and dihydro-pyridoquinazoline tricyclic lead scaffolds have emerged as novel PDE5A inhibitors for antihypertensive activity. The identified lead scaffolds may provide antihypertensive lead molecules after its optimization.

Molecular Docking Study for Analyzing the Inhibitory Effect of Anti-inflammatory Plant Compound Against Tumour Necrosis Factor (TNF-α)

2019 ◽  
Vol 14 (1) ◽  
pp. 85-90
Author(s):  
Sagarika Biswas
Keyword(s):  
Molecular Docking ◽  
Tumour Necrosis Factor ◽  
Tumour Necrosis ◽  
Docking Study ◽  
Developed Countries ◽  
Inhibitory Effect ◽  
Molecular Docking Study ◽  
Drug Designing ◽  
Anti Inflammatory ◽  
Necrosis Factor

Background: Rheumatoid Arthritis (RA) is an autoimmune disorder of symmetric synovial joints which is characterized by the chronic inflammation with 0.5-1% prevalence in developed countries. Presence of persistent inflammation is attributed to the major contribution of key inflammatory cytokine and tumour necrosis factor- alpha (TNF- &#945;). Recent drug designing studies are developing TNF-&#945; blockers to provide relief from the symptoms of the disease such as pain and inflammation. Available blockers are showing certain limitations such as it may enhance the rate of tuberculosis (TB) occurrence, lymphoma risk, cost issues and certain infections are major concern. Discussed limitations implicated a need of development of some alternative drugs which exhibit fewer side effects with low cost. Therefore, we have identified anti-inflammatory compounds in an underutilized fruit of Baccaurea sapida (B.sapida) in our previous studies. Among them quercetin have been identified as the most potent lead compound for drug designing studies of RA. </P><P> Methods: In the present article, characterization of quercetin has been carried out to check its drug likeliness and molecular docking study has been carried out between TNF- &#945; and quercetin by using AutoDock 4.2.1 software. Further, inhibitory effect of B. sapida fruit extract on RA plasma has been analysed through immunological assay ELISA. </P><P> Results: Our in-silico analysis indicated that quercetin showed non carcinogenic reaction in animal model and it may also cross the membrane barrier easily. We have studied the ten different binding poses and best binding pose of TNF-&#945; and quercetin showed -6.3 kcal/mol minimum binding energy and 23.94 &#181;M inhibitory constant. In addition to this, ELISA indicated 2.2 down regulated expression of TNF-&#945; in RA compared to control. </P><P> Conclusion: This study may further be utilized for the drug designing studies to reduce TNF-&#945; mediated inflammation in near future. This attempt may also enhance the utilization of this plant worldwide.

scholarly journals Important Role for Phylogenetically Invariant PP2Acα Active Site and C-Terminal Residues Revealed by Mutational Analysis in Saccharomyces cerevisiae

Genetics ◽  
2000 ◽  
Vol 156 (1) ◽  
pp. 21-29 ◽  
Author(s):  
David R H Evans ◽  
Brian A Hemmings
Keyword(s):  
Protein Interactions ◽  
Active Site ◽  
Protein Function ◽  
Mutational Analysis ◽  
Yeast Cells ◽  
Temperature Sensitive ◽  
Active Site Residues ◽  
Catalytic Function

Abstract PP2A is a central regulator of eukaryotic signal transduction. The human catalytic subunit PP2Acα functionally replaces the endogenous yeast enzyme, Pph22p, indicating a conservation of function in vivo. Therefore, yeast cells were employed to explore the role of invariant PP2Ac residues. The PP2Acα Y127N substitution abolished essential PP2Ac function in vivo and impaired catalysis severely in vitro, consistent with the prediction from structural studies that Tyr-127 mediates substrate binding and its side chain interacts with the key active site residues His-118 and Asp-88. The V159E substitution similarly impaired PP2Acα catalysis profoundly and may cause global disruption of the active site. Two conditional mutations in the yeast Pph22p protein, F232S and P240H, were found to cause temperature-sensitive impairment of PP2Ac catalytic function in vitro. Thus, the mitotic and cell lysis defects conferred by these mutations result from a loss of PP2Ac enzyme activity. Substitution of the PP2Acα C-terminal Tyr-307 residue by phenylalanine impaired protein function, whereas the Y307D and T304D substitutions abolished essential function in vivo. Nevertheless, Y307D did not reduce PP2Acα catalytic activity significantly in vitro, consistent with an important role for the C terminus in mediating essential protein-protein interactions. Our results identify key residues important for PP2Ac function and characterize new reagents for the study of PP2A in vivo.

scholarly journals CRISPR/Cas9-based generation of a recombinant double-reporter pseudorabies virus and its characterization in vitro and in vivo

2021 ◽  
Vol 52 (1) ◽  
Author(s):  
Peng-Fei Fu ◽  
Xuan Cheng ◽  
Bing-Qian Su ◽  
Li-Fang Duan ◽  
Cong-Rong Wang ◽  
...  
Keyword(s):  
Pseudorabies Virus ◽  
Fluorescent Protein ◽  
Antiviral Agents ◽  
Firefly Luciferase ◽  
Inhibitory Effect ◽  
Economic Losses ◽  
Green Fluorescent ◽  
Swine Herds

AbstractPseudorabies, caused by pseudorabies virus (PRV) variants, has broken out among commercial PRV vaccine-immunized swine herds and resulted in major economic losses to the pig industry in China since late 2011. However, the mechanism of virulence enhancement of variant PRV is currently unclear. Here, a recombinant PRV (rPRV HN1201-EGFP-Luc) with stable expression of enhanced green fluorescent protein (EGFP) and firefly luciferase as a double reporter virus was constructed on the basis of the PRV variant HN1201 through CRISPR/Cas9 gene-editing technology coupled with two sgRNAs. The biological characteristics of the recombinant virus and its lethality to mice were similar to those of the parental strain and displayed a stable viral titre and luciferase activity through 20 passages. Moreover, bioluminescence signals were detected in mice at 12 h after rPRV HN1201-EGFP-Luc infection. Using the double reporter PRV, we also found that 25-hydroxycholesterol had a significant inhibitory effect on PRV both in vivo and in vitro. These results suggested that the double reporter PRV based on PRV variant HN1201 should be an excellent tool for basic virology studies and evaluating antiviral agents.

Sign in / Sign up

Export Citation Format

Share Document