Discovery of Two Brominated Oxindole Alkaloids as Staphylococcal DNA Gyrase and Pyruvate Kinase Inhibitors via Inverse Virtual Screening

In the present study, a small marine-derived natural products library was assessed for antibacterial potential. Among 36 isolated compounds, a number of bis-indole derivatives exhibited growth-inhibitory activity towards Gram-positive strains (Bacillus subtilis and multidrug-resistant Staphylococcus aureus). 5- and 6-trisindoline (5-Tris and 6-Tris) were the most active derivatives (minimum inhibitory concentration, MIC, 4–8 µM) that were subsequently selected for anti-biofilm activity evaluation. Only 5-Tris was able to inhibit the staphylococcal biofilm formation starting at a 5 µM concentration. In order to investigate their possible molecular targets, both natural products were subjected to in silico inverse virtual screening. Among 20 target proteins, DNA gyrase and pyruvate kinase were the most likely to be involved in the observed antibacterial and anti-biofilm activities of both selected natural products. The in vitro validation and in silico binding mode studies revealed that 5-Tris could act as a dual enzyme inhibitor (IC50 11.4 ± 0.03 and 6.6 ± 0.05 µM, respectively), while 6-Tris was a low micromolar gyrase-B inhibitor (IC50 2.1 ± 0.08 µM), indicating that the bromine position plays a crucial role in the determination of the antibacterial lead compound inhibitory activity.

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In Silico De Novo Curcuminoid Derivatives From the Compound Library of Natural Products Research Laboratories Inhibit COVID-19 3CLpro Activity

Natural Product Communications ◽

10.1177/1934578x20953262 ◽

2020 ◽

Vol 15 (9) ◽

pp. 1934578X2095326

Author(s):

Jai-Sing Yang ◽

Jo-Hua Chiang ◽

Shih‑Chang Tsai ◽

Yuan-Man Hsu ◽

Da-Tian Bau ◽

...

Keyword(s):

Natural Products ◽

Virtual Screening ◽

Binding Affinity ◽

High Throughput ◽

In Silico ◽

De Novo ◽

Compound Library ◽

Therapeutic Success ◽

High Throughput Virtual Screening

The coronavirus disease 2019 (COVID‐19) outbreak caused by the 2019 novel coronavirus (2019-nCOV) is becoming increasingly serious. In March 2019, the Food and Drug Administration (FDA) designated remdesivir for compassionate use to treat COVID-19. Thus, the development of novel antiviral agents, antibodies, and vaccines against COVID-19 is an urgent research subject. Many laboratories and research organizations are actively investing in the development of new compounds for COVID-19. Through in silico high-throughput virtual screening, we have recently identified compounds from the compound library of Natural Products Research Laboratories (NPRL) that can bind to COVID-19 3Lpro polyprotein and block COVID-19 3Lpro activity through in silico high-throughput virtual screening. Curcuminoid derivatives (including NPRL334, NPRL339, NPRL342, NPRL346, NPRL407, NPRL415, NPRL420, NPRL472, and NPRL473) display strong binding affinity to COVID-19 3Lpro polyprotein. The binding site of curcuminoid derivatives to COVID-19 3Lpro polyprotein is the same as that of the FDA-approved human immunodeficiency virus protease inhibitor (lopinavir) to COVID-19 3Lpro polyprotein. The binding affinity of curcuminoid derivatives to COVID-19 3Lpro is stronger than that of lopinavir and curcumin. Among curcuminoid derivatives, NPRL-334 revealed the strongest binding affinity to COVID-19 3Lpro polyprotein and is speculated to have an anti-COVID-19 effect. In vitro and in vivo ongoing experiments are currently underway to confirm the present findings. This study sheds light on the drug design for COVID-19 3Lpro polyprotein. Basing on lead compound development, we provide new insights on inhibiting COVID-19 attachment to cells, reducing COVID-19 infection rate and drug side effects, and increasing therapeutic success rate.

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Methoxyflavones from Marcetia taxifolia as HIV-1 Reverse Transcriptase Inhibitors

Natural Product Communications ◽

10.1177/1934578x1701201104 ◽

2017 ◽

Vol 12 (11) ◽

pp. 1934578X1701201 ◽

Cited By ~ 1

Author(s):

Joseph T Ortega ◽

María Luisa Serrano ◽

Alírica I Suárez ◽

Jani Baptista ◽

Flor H Pujol ◽

...

Keyword(s):

Virtual Screening ◽

Reverse Transcriptase ◽

Inhibitory Activity ◽

In Silico ◽

Antitumor Agents ◽

In Silico Prediction ◽

Reverse Transcriptase Inhibitors ◽

Hiv 1

Methoxyflavones are flavonoid widely distributed in plants and has been reported as potent antitumor agents and some of them have shown activity against HIV-1. In this work, two methoxyflavones isolated from Marcetia taxifolia were evaluated in vitro and in silico as HIV-1 inhibitors. Pentamethoxyflavone (5,3’-dihydroxy-3,6,7,8,4’-pentamethoxyflavone) (PMF) and Hexamethoxyflavone (5-Hydroxy-3,6,7,8,3’,4’-hexamethoxyflavone) (HMF) showed activity against HIV-1. The EC50 for HMF was 0.05 μM and 0.04 μM for PMF. The methoxyflavones also inhibited HIV-1 reverse transcriptase (RT), with an IC50 of 4.1 μM for HMF and 0.4 μM for PMF. PMF exhibited an IC50 lower than nevirapine (1.4 μM). These results are in agreement with the in silico prediction for the interaction of these flavonoids with RT. Furthermore, the effect of some methoxyflavones with different patterns of methoxylation was evaluated on RT activity in a virtual screening; found that the inhibitory activity was inversely proportional to the degree of methoxylation.

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Identification of Broad-Spectrum MMP Inhibitors by Virtual Screening

Molecules ◽

10.3390/molecules26154553 ◽

2021 ◽

Vol 26 (15) ◽

pp. 4553

Author(s):

Aleix Gimeno ◽

Doretta Cuffaro ◽

Elisa Nuti ◽

María José Ojeda-Montes ◽

Raúl Beltrán-Debón ◽

...

Keyword(s):

Extracellular Matrix ◽

Natural Products ◽

Virtual Screening ◽

Broad Spectrum ◽

In Silico ◽

Mmp Inhibitors ◽

Bioactivity Assay ◽

The Family ◽

Skin Wrinkling

Matrix metalloproteinases (MMPs) are the family of proteases that are mainly responsible for degrading extracellular matrix (ECM) components. In the skin, the overexpression of MMPs as a result of ultraviolet radiation triggers an imbalance in the ECM turnover in a process called photoaging, which ultimately results in skin wrinkling and premature skin ageing. Therefore, the inhibition of different enzymes of the MMP family at a topical level could have positive implications for photoaging. Considering that the MMP catalytic region is mostly conserved across different enzymes of the MMP family, in this study we aimed to design a virtual screening (VS) workflow to identify broad-spectrum MMP inhibitors that can be used to delay the development of photoaging. Our in silico approach was validated in vitro with 20 VS hits from the Specs library that were not only structurally different from one another but also from known MMP inhibitors. In this bioactivity assay, 18 of the 20 compounds inhibit at least one of the assayed MMPs at 100 μM (with 5 of them showing around 50% inhibition in all the tested MMPs at this concentration). Finally, this VS was used to identify natural products that have the potential to act as broad-spectrum MMP inhibitors and be used as a treatment for photoaging.

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QSAR-Based Virtual Screening of Natural Products Database for Identification of Potent Antimalarial Hits

Biomolecules ◽

10.3390/biom11030459 ◽

2021 ◽

Vol 11 (3) ◽

pp. 459

Author(s):

Letícia Tiburcio Ferreira ◽

Joyce V. B. Borba ◽

José Teófilo Moreira-Filho ◽

Aline Rimoldi ◽

Carolina Horta Andrade ◽

...

Keyword(s):

Natural Products ◽

Virtual Screening ◽

Low Income ◽

In Silico ◽

Biologically Active ◽

Drug Resistant ◽

Quantitative Structure ◽

Physiologically Based Pharmacokinetic ◽

Physiologically Based

With about 400,000 annual deaths worldwide, malaria remains a public health burden in tropical and subtropical areas, especially in low-income countries. Selection of drug-resistant Plasmodium strains has driven the need to explore novel antimalarial compounds with diverse modes of action. In this context, biodiversity has been widely exploited as a resourceful channel of biologically active compounds, as exemplified by antimalarial drugs such as quinine and artemisinin, derived from natural products. Thus, combining a natural product library and quantitative structure–activity relationship (QSAR)-based virtual screening, we have prioritized genuine and derivative natural compounds with potential antimalarial activity prior to in vitro testing. Experimental validation against cultured chloroquine-sensitive and multi-drug-resistant P. falciparum strains confirmed the potent and selective activity of two sesquiterpene lactones (LDT-597 and LDT-598) identified in silico. Quantitative structure–property relationship (QSPR) models predicted absorption, distribution, metabolism, and excretion (ADME) and physiologically based pharmacokinetic (PBPK) parameters for the most promising compound, showing that it presents good physiologically based pharmacokinetic properties both in rats and humans. Altogether, the in vitro parasite growth inhibition results obtained from in silico screened compounds encourage the use of virtual screening campaigns for identification of promising natural compound-based antimalarial molecules.

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Evaluation of Phytopolyphenols for their gp120-CD4 Binding Inhibitory Properties by In Silico Molecular Modelling & In Vitro Cell Line Studies

Current HIV Research ◽

10.2174/1570162x17666190611121627 ◽

2019 ◽

Vol 17 (2) ◽

pp. 102-113 ◽

Cited By ~ 3

Author(s):

Amit Mirani ◽

Harish Kundaikar ◽

Shilpa Velhal ◽

Vainav Patel ◽

Atmaram Bandivdekar ◽

...

Keyword(s):

Molecular Docking ◽

Gallic Acid ◽

Cell Line ◽

Ellagic Acid ◽

Inhibitory Activity ◽

In Silico ◽

Early Stage ◽

Binding Mode ◽

Hiv 1

Background:Lack of effective early-stage HIV-1 inhibitor instigated the need for screening of novel gp120-CD4 binding inhibitor. Polyphenols, a secondary metabolite derived from natural sources are reported to have broad spectrum HIV-1 inhibitory activity. However, the gp120-CD4 binding inhibitory activity of polyphenols has not been analysed in silico yet.Objectives:To establish the usage of phytopolyphenols (Theaflavin, Epigallocatechin (EGCG), Ellagic acid and Gallic acid) as early stage HIV-1 inhibitor by investigating their binding mode in reported homology of gp120-CD4 receptor complex using in silico screening studies and in vitro cell line studies.Methods:The in silico molecular docking and molecular simulation studies were performed using Schrödinger 2013-2 suite installed on Fujitsu Celsius Workstation. The in vitro cell line studies were performed in the TZM-bl cell line using MTT assay and β-galactosidase assay.Results:The results of molecular docking indicated that Theaflavin and EGCG exhibited high XP dock score with binding pose exhibiting Van der Waals interaction and hydrophobic interaction at the deeper site in the Phe43 cavity with Asp368 and Trp427. Both Theaflavin and EGCG form a stable complex with the prepared HIV-1 receptor and their binding mode interaction is within the vicinity 4 Å. Further, in vitro cell line studies also confirmed that Theaflavin (SI = 252) and EGCG (SI = 138) exert better HIV-1 inhibitory activity as compared to Ellagic acid (SI = 30) and Gallic acid (SI = 34).Conclusions:The results elucidate a possible binding mode of phytopolyphenols, which pinpoints their plausible mechanism and directs their usage as early stage HIV-1 inhibitor.

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Discovery of New AKT1 Inhibitors by Combination of In silico Structure Based Virtual Screening Approaches and Biological Evaluations

10.26434/chemrxiv.7591202 ◽

2019 ◽

Author(s):

Filip Fratev ◽

Denisse A. Gutierrez ◽

Renato J. Aguilera ◽

suman sirimulla

Keyword(s):

Virtual Screening ◽

Success Rate ◽

Protein Interactions ◽

In Silico ◽

Biological Data ◽

In Vitro Binding ◽

Vitro Binding ◽

Screening Protocol ◽

Screening Approaches

AKT1 is emerging as a useful target for treating cancer. Herein, we discovered a new set of ligands that inhibit the AKT1, as shown by in vitro binding and cell line studies, using a newly designed virtual screening protocol that combines structure-based pharmacophore and docking screens. Taking together with the biological data, the combination of structure based pharamcophore and docking methods demonstrated reasonable success rate in identifying new inhibitors (60-70%) proving the success of aforementioned approach. A detail analysis of the ligand-protein interactions was performed explaining observed activities.<br>

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Design, Synthesis, Molecular Docking and Biological Evaluation of 1-(benzo[d]thiazol-2-ylamino)(phenyl)methyl)naphthalen-2-ol Derivatives as Antiproliferative Agents

Letters in Organic Chemistry ◽

10.2174/1570178616666190408101233 ◽

2019 ◽

Vol 16 (10) ◽

pp. 837-845

Author(s):

Sandhya Jonnala ◽

Bhaskar Nameta ◽

Murthy Chavali ◽

Rajashaker Bantu ◽

Pallavi Choudante ◽

...

Keyword(s):

Molecular Docking ◽

Inhibitory Activity ◽

Chinese Hamster Ovary Cells ◽

Chinese Hamster ◽

Mouse Skin ◽

Coupling Reaction ◽

Binding Mode ◽

Biological Evaluation ◽

Design Synthesis

A class of 1-((benzo[d]thiazol-2-ylamino)(phenyl)methyl)naphthalen-2-ol derivatives (4a-t) has been synthesized in good yields through a three component coupling reaction. The newly synthesized compounds were evaluated for their in vitro antiproliferative activity against five cell lines such as DU145 (human prostate cancer), MDA-MB-B231 (human breast cancer), SKOV3 (human ovarian cancer), B16-F10 (mouse skin melanoma) and CHO-K1 (Chinese hamster ovary cells), a noncancerous cell line. In vitro inhibitory activity indicates that compounds 4a, 4b, 4c, 4d, 4g, 4j, and 4o exhibited potent anti-proliferative behavior. Among them, compounds 4g, 4j and 4o found to be the most active members exhibiting remarkable growth inhibitory activity. Molecular docking facilitates to investigate the probable binding mode and key active site interactions in tubulins α and β proteins. The docking results are complementary to experimental results.

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Design, Synthesis and In-Vitro Biological Activity of Some New 1,3-Thiazolidine-4-One Derivatives as Chemotherapeutic Agents Using Virtual Screening Strategies

Current Computer - Aided Drug Design ◽

10.2174/1573409916666200116102359 ◽

2020 ◽

Vol 16 ◽

Author(s):

Pragya Nayak ◽

Monica Kachroo

Keyword(s):

Pseudomonas Aeruginosa ◽

Virtual Screening ◽

In Silico ◽

Cancer Cell Line ◽

Inhibitory Response ◽

Chemotherapeutic Agents ◽

Acceptor Site ◽

Hydrogen Bond Acceptor ◽

Screening Strategies

: A series of new heteroaryl thiazolidine-4-one derivatives were designed and subjected to in-silico prioritization using various virtual screening strategies. Two series of thiazolidinone derivatives were synthesized and screened for their in-vitro antitubercular, anticancer, antileishmanial and antibacterial (Staphylococcus aureus; Streptococcus pneumonia; Escherichia coli; Pseudomonas aeruginosa) activities. The compounds with electronegative substitutions exhibited positive antitubercular activity, the derivatives possessing a methyl substitution exhibited good inhibitory response against breast cancer cell line MCF-7 while the compounds possessing a hydrogen bond acceptor site like hydroxyl and methoxy substitution in their structures exhibited good in-vitro antileishmanial activity. Some compounds exhibited potent activity against gram positive bacteria Pseudomonas aeruginosa as compared to the standards. Altogether, the designed compounds exhibited good in-vitro anti-infective potential which was in good agreement with the in-silico predictions and they can be developed as important lead molecules for anti-infective and chemotherapeutic drug research.

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Virtual Screening, Molecular docking and in-silico ADME-Tox analysis for identification of potential main protease (Mpro) enzyme inhibitors

Anti-Infective Agents ◽

10.2174/2211352518999201208201854 ◽

2020 ◽

Vol 18 ◽

Author(s):

Debadash Panigrahi ◽

Ganesh Prasad Mishra

Keyword(s):

Molecular Docking ◽

Virtual Screening ◽

In Silico ◽

Data Bank ◽

Future Research ◽

Reference Compound ◽

Unexpected Death ◽

Main Protease ◽

In Silico Admet

Objective:: Recent pandemic caused by SARS-CoV-2 described in Wuhan China in December-2019 spread widely almost all the countries of the world. Corona virus (COVID-19) is causing the unexpected death of many peoples and severe economic loss in several countries. Virtual screening based on molecular docking, drug-likeness prediction, and in silico ADMET study has become an effective tool for the identification of small molecules as novel antiviral drugs to treat diseases. Methods:: In the current study, virtual screening was performed through molecular docking for identifying potent inhibitors against Mpro enzyme from the ZINC library for the possible treatment of COVID-19 pandemic. Interestingly, some compounds are identified as possible anti-covid-19 agents for future research. 350 compounds were screened based on their similarity score with reference compound X77 from ZINC data bank and were subjected to docking with crystal structure available of Mpro enzyme. These compounds were then filtered by their in silico ADME-Tox and drug-likeness prediction values. Result:: Out of these 350 screened compounds, 10 compounds were selected based on their docking score and best docked pose in comparison to the reference compound X77. In silico ADME-Tox and drug likeliness predictions of the top compounds were performed and found to be excellent results. All the 10 screened compounds showed significant binding pose with the target enzyme main protease (Mpro) enzyme and satisfactory pharmacokinetic and toxicological properties. Conclusion:: Based on results we can suggest that the identified compounds may be considered for therapeutic development against the COVID-19 virus and can be further evaluated for in vitro activity, preclinical, clinical studies and formulated in a suitable dosage form to maximize their bioavailability.

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Potential Anticancer Lipoxygenase Inhibitors from the Red Sea-Derived Brown Algae Sargassum cinereum: An In-Silico-Supported In-Vitro Study

Antibiotics ◽

10.3390/antibiotics10040416 ◽

2021 ◽

Vol 10 (4) ◽

pp. 416

Author(s):

Sami I. Alzarea ◽

Abeer H. Elmaidomy ◽

Hani Saber ◽

Arafa Musa ◽

Mohammad M. Al-Sanea ◽

...

Keyword(s):

Red Sea ◽

Antiproliferative Activity ◽

Inhibitory Activity ◽

Brown Algae ◽

In Silico ◽

Active Sites ◽

In Vitro Study ◽

Lipoxygenase Inhibitors ◽

Phytochemical Investigation

LC-MS-assisted metabolomic profiling of the Red Sea-derived brown algae Sargassum cinereum “Sargassaceae” dereplicated eleven compounds 1–11. Further phytochemical investigation afforded two new aryl cresol 12–13, along with eight known compounds 14–21. Both new metabolites, along with 19, showed moderate in vitro antiproliferative activity against HepG2, MCF-7, and Caco-2. Pharmacophore-based virtual screening suggested both 5-LOX and 15-LOX as the most probable target linked to their observed antiproliferative activity. The in vitro enzyme assays revealed 12 and 13 were able to inhibit 5-LOX more preferentially than 15-LOX, while 19 showed a convergent inhibitory activity toward both enzymes. Further in-depth in silico investigation revealed the molecular interactions inside both enzymes’ active sites and explained the varying inhibitory activity for 12 and 13 toward 5-LOX and 15-LOX.

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