@article { ISI:000257626900005, title = {Bactericidal activity of 2-nitroimidazole against the active replicating stage of mycobacterium bovis BCG and mycobacterium tuberculosis with intracellular efficacy in THP-1 macrophages}, journal = {International Journal of Antimicrobial Agents}, volume = {32}, number = {1}, year = {2008}, month = {JUL}, pages = {40-45}, publisher = {ELSEVIER SCIENCE BV}, type = {Article}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

This study evaluated the antituberculous potential of 2-nitroimidazole under in vitro conditions. Minimal bactericidal concentrations of the compound against actively replicating Mycobacterium bovis BCG and Mycobacterium tuberculosis H37Ra were found to be 0.226 mu g/mL and 0.556 mu g/mL in enriched and minimal medium, respectively. Minimal inhibitory concentrations were \> 100 times lower than reported antituberculous nitroimidazoles such as nitrofurantoin and furaltadone, indicating the greater potential of 2-nitroimidazole. No discernible effect of 2-nitroimidazole was seen on saprophytic Mycobacterium smegmatis and the representative bacterial strain Escherichia coli DH5 alpha, indicating the specificity of the molecule against tuberculous mycobacteria. The compound was also found to be effective against M. tuberculosis in the intracellular environment of the human monocytic cell line THP-1, with a reduction in viability of bacilli by 2.5 log after 144 h of incubation at a concentration of 0.113 mu g/mL. A five-fold higher concentration (0.565 mu g/mL) of 2-nitroimidazole sterilised the macrophages of intracellular pathogens within 192 h, without affecting the host. However, 2-nitroimidazole was unable to affect significantly the viability of dormant non-replicating bacilli of M. bovis BCG and M. tuberculosis in Wayne{\textquoteright}s in vitro model. Overall, the results indicate that 2-nitroimidazole is a potent antituberculous agent active against the organism{\textquoteright}s active replicating stage, with promising intracellular efficacy as well. (c) 2008 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.

}, keywords = {2-nitroimidazole, antimycobacterial agents, nitroimidazoles, THP-1 macrophage, tuberculosis}, issn = {0924-8579}, doi = {10.1016/j.ijantimicag.2008.02.022}, author = {Khan, Arshad and Sarkar, Sampa and Sarkar, Dhiman} } @article { ISI:000255300600009, title = {Simple whole cell based high throughput screening protocol using Mycobacterium bovis BCG for inhibitors against dormant and active tubercle bacilli}, journal = {Journal of Microbiological Methods}, volume = {73}, number = {1}, year = {2008}, month = {APR}, pages = {62-68}, publisher = {ELSEVIER SCIENCE BV}, type = {Article}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

This study aimed at developing a whole cell based high throughput screening protocol to identify inhibitors against both active and dormant tubercle bacilli. A respiratory type of nitrate reductase (NarGHJI), which was induced during dormancy, could reflect the viability of dormant bacilli of Mycobacterium bovis BCG in microplate adopted model of in vitro dormancy. Correlation between reduction in viability and nitrate reductase activity was seen clearly when dormant stage inhibitor metronidazole and itaconic anhydride were applied in this in vitro microplate model. Active replicating stage could also be monitored in the same assay by measuring the A(620) of the culture. MIC values of 0.08, 0.075, 0.3 and 3.0 mu g/ml, determined through monitoring A(620) in this assay for rifampin, isoniazid, streptomycin and ethambutol respectively, were well in agreement with previously reported by BACTEC and Bio-Siv assays. S/N ratio and Z{\textquoteright} factor for the assay were 8.5 and 0.81 respectively which indicated the robustness of the protocol. Altogether the assay provides an easy, inexpensive, rapid, robust and high content screening too] to search novel antitubercular molecules against both active and dormant bacilli. (C) 2008 Elsevier B.V. All rights reserved.

}, keywords = {high throughput screening, tuberculosis, Wayne{\textquoteright}s dormancy model, whole cell based assay}, issn = {0167-7012}, doi = {10.1016/j.mimet.2008.01.015}, author = {Khan, Arshad and Sarkar, Dhiman} } @article { ISI:000363379900001, title = {Cell scale host-pathogen modeling: another branch in the evolution of constraint-based methods}, journal = {Frontiers in Microbiology}, volume = {6}, year = {2015}, month = {OCT}, pages = {Article Number: 1032}, publisher = {FRONTIERS MEDIA SA}, address = {PO BOX 110, EPFL INNOVATION PARK, BUILDING I, LAUSANNE, 1015, SWITZERLAND}, abstract = {

Constraint-based models have become popular methods for systems biology as they enable the integration of complex, disparate datasets in a biologically cohesive framework that also supports the description of biological processes in terms of basic physicochemical constraints and relationships. The scope, scale, and application of genome scale models have grown from single cell bacteria to multi cellular interaction modeling; host-pathogen modeling represents one of these examples at the current horizon of constraint-based methods. There are now a small number of examples of host-pathogen constraint-based models in the literature, however there has not yet been a definitive description of the methodology required for the functional integration of genome scale models in order to generate simulation capable host-pathogen models. Herein we outline a systematic procedure to produce functional host-pathogen models, highlighting steps which require debugging and iterative revisions in order to successfully build a functional model. The construction of such models will enable the exploration of host-pathogen interactions by leveraging the growing wealth of omic data in order to better understand mechanism of infection and identify novel therapeutic strategies.

}, keywords = {constraint-based model, flux balance analysis, host-pathogen, mathematical models, omics-technologies, optimization methods, salmonella typhimurium, tuberculosis}, issn = {1664-302X}, doi = {10.3389/fmicb.2015.01032}, author = {Jamshidi, Neema and Raghunathan, Anu} } @article { ISI:000360705500008, title = {Chemical and biological metal nanoparticles as antimycobacterial agents: a comparative study}, journal = {International Journal of Antimicrobial Agents}, volume = {46}, number = {2}, year = {2015}, month = {AUG}, pages = {183-188}, publisher = {ELSEVIER SCIENCE BV}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

Resistance among mycobacteria leading to multidrug-resistant and extensively drug-resistant tuberculosis is a major threat. However, nanotechnology has provided new insights in drug delivery and medicine development. This is the first comparative report to determine the activity of chemically and biologically synthesised silver nanoparticles (AgNPs) and gold nanoparticles (AuNPs) against mycobacteria. Screening data revealed the high mycobactericidal efficiency of AgNPs, with minimum inhibitory concentrations (MICs) of \<3 mu g/mL, whereas no such activity was exhibited by AuNPs at concentrations up to 100 mu g/mL. Moreover, in vitro and ex vivo THP-1 infection model assays showed greater efficacy of chemical AgNPs compared with biogenic AgNPs to inhibit active and dormant stage mycobacterial growth. Up to 40\% cytotoxicity against human cell lines was observed at a AgNP concentration of 10 x MIC (30 mu g/mL) after 48 h. AgNPs were shown to have more specificity towards mycobacteria than towards other Gram-negative and Gram-positive pathogenic bacteria. The selectivity index was found to be in the range of 11-23, indicating the potential of these nanoparticles for use in developing new therapeutics for tuberculosis. (C) 2015 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.

}, keywords = {Antibiotic resistance, Antimycobacterial agent, Cytotoxicity, Mycobacteria, Nanoparticles, tuberculosis}, issn = {0924-8579}, doi = {10.1016/j.ijantimicag.2015.03.014}, author = {Singh, Richa and Nawale, Laxman U. and Arkile, Manisha A. and Shedbalkar, Utkarsha U. and Wadhwani, Sweety A. and Sarkar, Dhiman and Chopade, Balu Ananda} } @article { ISI:000357468200016, title = {Discovery of rimonabant and its potential analogues as anti-TB drug candidates}, journal = {Medicinal Chemistry Research}, volume = {24}, number = {7}, year = {2015}, month = {JUL}, pages = {2960-2971}, publisher = {SPRINGER BIRKHAUSER}, address = {233 SPRING STREET, 6TH FLOOR, NEW YORK, NY 10013 USA}, abstract = {

Rimonabant and its analogues have been synthesized in moderate to good yields using a simple synthetic route. All the newly synthesized compounds were subjected to in vitro screening against M. tuberculosis and M. smegmatis. The most potent analogue JMG-14 exhibits MIC value of 3.13 compared to 3.25 and 50 A mu g/ml for ethambutol and pyrazinamide, respectively. The molecular docking reveals that pyrazole ring, number and position of halogen atoms play a crucial role in deciding interactions with MTCYP-121. These findings open up a new avenue in the search of potent anti-TB drugs with rimonabant and its novel analogue JMG-14 as lead molecules.

}, keywords = {Diaryl pyrazoles, H37Rv, MTCYP-121, Mycobacterium tuberculosis, Rimonabant, tuberculosis}, issn = {1054-2523}, doi = {10.1007/s00044-015-1346-4}, author = {Gajbhiye, J. M. and More, Namita A. and Patil, Manoj D. and Ummanni, R. and Kotapalli, S. S. and Yogeeswari, P. and Sriram, D. and Masand, Vijay H.} } @article { ISI:000356251500001, title = {Qualitative and quantitative proteomic analysis of vitamin C induced changes in mycobacterium smegmatis}, journal = {Frontiers in Microbiology}, volume = {6}, year = {2015}, month = {MAY}, pages = {Article Number: 451}, publisher = {FRONTIERS RESEARCH FOUNDATION}, address = {PO BOX 110, LAUSANNE, 1015, SWITZERLAND}, abstract = {

Vitamin C is a critical dietary nutrient in human which has a wide range of regulatory effects on gene expression and physiology of Mycobacterium tuberculosis that leads to a dormant drug-tolerant phenotype. In the presence of iron, vitamin C shows a high bactericidal activity even in the drug resistant phenotype of M. tuberculosis. The regulatory mechanisms underlying vitamin C induced adaptations are largely unknown due to lack of functional genomics data in this field. In this study, we attempt to characterize the direct effect of vitamin C treatment on the physiology of actively growing Mycobacterium smegmatis. The study chose M. smegmatis as it is a fast-growing bacterium and a non-pathogenic model system which shares many physiological features with the pathogenic M. tuberculosis including dormancy and its regulation. The proteomic adaptation of M. smegmatis on vitamin C treatment demonstrates the important changes in cellular and metabolic process such as reversal of tricarboxylic acid cycle, decrease in ATP synthesis, decrease in iron acquisition and storage, and induction of dormancy regulators WhiB3, PhoP, and Lsr2.

}, keywords = {dormancy, Mycobacterium smegmatis, proteomics, tuberculosis, vitamin C}, issn = {1664-302X}, doi = {10.3389/fmicb.2015.00451}, author = {Mishra, Abhishek and Sarkar, Dhiman} } @article { ISI:000375559600001, title = {Phytogenic silver, gold, and bimetallic nanoparticles as novel antitubercular agents}, journal = {International Journal of Nanomedicine}, volume = {11}, year = {2016}, month = {MAY}, pages = {1889{\textemdash}1897}, publisher = {DOVE MEDICAL PRESS LTD}, address = {PO BOX 300-008, ALBANY, AUCKLAND 0752, NEW ZEALAND}, abstract = {

Purpose: Multi- and extensively drug-resistant tuberculosis (TB) is a global threat to human health. It requires immediate action to seek new antitubercular compounds and devise alternate strategies. Nanomaterials, in the present scenario, have opened new avenues in medicine, diagnosis, and therapeutics. In view of this, the current study aims to determine the efficacy of phytogenic metal nanoparticles to inhibit mycobacteria. Methods: Silver (AgNPs), gold (AuNPs), and gold-silver bimetallic (Au-AgNPs) nanoparticles synthesized from medicinal plants, such as Barleria prionitis, Plumbago zeylanica, and Syzygium cumini, were tested against Mycobacterium tuberculosis and M. bovis BCG. In vitro and ex vivo macrophage infection model assays were designed to determine minimum inhibitory concentration (MIC) and half maximal inhibitory concentration of nanoparticles. Microscopic analyses were carried out to demonstrate intracellular uptake of nanoparticles in macrophages. Besides this, biocompatibility, specificity, and selectivity of nanoparticles were also established with respect to human cell lines. Results: Au-AgNPs exhibited highest antitubercular activity, with MIC of \<2.56 mu g/mL, followed by AgNPs. AuNPs did not show such activity at concentrations of up to 100 mu g/mL. In vitro and ex vivo macrophage infection model assays revealed the inhibition of both active and dormant stage mycobacteria on exposure to Au-AgNPs. These nanoparticles were capable of entering macrophage cells and exhibited up to 45\% cytotoxicity at 30 mu g/mL (ten times MIC concentration) after 48 hours. Among these, Au-AgNPs synthesized from S. cumini were found to be more specific toward mycobacteria, with their selectivity index in the range of 94-108. Conclusion: This is the first study to report the antimycobacterial activity of AuNPs, AgNPs, and Au-AgNPs synthesized from medicinal plants. Among these, Au-AgNPs from S. cumini showed profound efficiency, specificity, and selectivity to kill mycobacteria. These should be investigated further to develop novel TB nanoantibiotics.

}, keywords = {Antimycobacterial agent, Cytotoxicity, drug resistance, Mycobacteria, Nanoparticles, tuberculosis}, issn = {1178-2013}, doi = {10.2147/IJN.S102488}, author = {Singh, Richa and Nawale, Laxman and Arkile, Manisha A. and Wadhwani, Sweety and Shedbalkar, Utkarsha and Chopade, Snehal and Sarkar, Dhiman and Chopade, Balu Ananda} } @article { ISI:000373739700025, title = {Synthesis and docking studies of pyrazine-thiazolidinone hybrid scaffold targeting dormant tuberculosis}, journal = {Bioorganic \& Medicinal Chemistry Letters}, volume = {26}, number = {9}, year = {2016}, month = {MAY}, pages = {2224-2228}, publisher = {PERGAMON-ELSEVIER SCIENCE LTD}, address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND}, abstract = {

The persistence of Mycobacterium tuberculosis (MTB) in dormant stage assists the pathogen to develop resistance against current antimycobactrial drugs. To address this issue, we report herein the synthesis of N-(4-oxo-2 substituted thiazolidin-3yl) pyrazine-2-carbohydrazide derivatives designed by following the molecular hybridization approach using pyrazine and thiazolidenone scaffolds. The compounds were evaluated against MTB H37Ra and Mycobacterium bovis BCG in dormancy model. Most of the compounds had IC50 values in 0.3-1 mu g/ml range. The active compounds were further tested for anti-proliferative activity against THP-1, Panc-1, A549, and MCF-7 cell lines using MTT assay and exhibited no significant cytotoxicity. We also report molecular docking studies using active analogs and MTB Decaprenylphosphoryl-beta-D-ribose-2{\textquoteright}-epimerase (DprE1) to rationalize the biological activity and to provide an insight into the probable mechanism of action and binding mode of hybridized structures. The results obtained validate the use of molecular hybridization approach and also suggest that reported compounds can provide a novel pharmacophore to synthesize lead compounds against dormat MTB. (C) 2016 Elsevier Ltd. All rights reserved.

}, keywords = {docking, Dormant, Hybrid design, Pyrazine, Thiazolidenone, tuberculosis}, issn = {0960-894X}, doi = {10.1016/j.bmcl.2016.03.055}, author = {Chitre, T. S. and Asgaonkar, K. D. and Miniyar, P. B. and Dharme, A. B. and Arkile, Manisha A. and Yeware, A. and Sarkar, Dhiman and Khedkar, Vijay M. and Jha, Prakash C.} } @article {43949, title = {Assessing therapeutic potential of molecules: molecular property diagnostic suite for tuberculosis}, journal = {Journal of Chemical Sciences}, volume = {129}, year = {2017}, month = {MAY}, pages = {515-531}, type = {Article}, abstract = {

Abstract: Molecular Property Diagnostic Suite (MPDS TB) is a web tool (http://mpds.osdd.net) designed to assist the in silico drug discovery attempts towards Mycobacterium tuberculosis (Mtb). MPDS TB tool has nine modules which are classified into data library (1{\textendash}3), data processing (4{\textendash}5) and data analysis (6{\textendash}9). Module 1 is a repository of literature and related information available on the Mtb. Module 2 deals with the protein target analysis of the chosen disease area. Module 3 is the compound library consisting of 110.31 million unique molecules generated from public domain databases and custom designed search tools. Module 4 contains tools for chemical file format conversions and 2D to 3D coordinate conversions. Module 5 helps in calculating the molecular descriptors. Module 6 specifically handles QSAR model development tools using descriptors generated in the Module 5. Module 7 integrates the AutoDock Vina algorithm for docking, while module 8 provides screening filters. Module 9 provides the necessary visualization tools for both small and large molecules. The workflow-based open source web portal, MPDS TB 1.0.1 can be a potential enabler for scientists engaged in drug discovery in general and in anti-TB research in particular. Graphical Abstract: SYNOPSIS: A web-based MPDS TB Galaxy tool is developed for assessing therapeutic potential of molecules. MPDS TB is categorized into Data Library, Data Processing and Data Analysis. It can be a potential enabler for scientists engaged in drug discovery in general and in anti-TB research in particular. [Figure not available: see fulltext.] {\textcopyright} 2017, Indian Academy of Sciences.

}, keywords = {chemical analysis, Chemoinformatics, computational chemistry, Diagnosis, Drug discovery portal, Information analysis, Libraries, Molecular graphics, Molecules, Neglected diseases, Open science, Portals, tuberculosis, Web-based technology, Websites}, issn = {0974-3626}, doi = {10.1007/s12039-017-1268-4}, author = {Gaur, A. S. and Bhardwaj, A. and Sharma, A. and John, L. and Vivek, M. R. and Tripathi, N. and Bharatam, P. V. and Kumar, R. and Janardhan, S. and Mori, A. and Banerji, A. and Lynn, A. M. and Hemrom, A. J. and Passi, A. and Singh, A. and Kumar, A. and Muvva, C. and Madhuri, C. and Choudhury, C. and Kumar, D. A. and Pandit, D. and Bharti, D. R. and Kumar, D. and Singam, E. A. and Raghava, G. P. and Sailaja, H. and Jangra, H. and Raithatha, K. and Tanneeru, K. and Chaudhary, K. and Karthikeyan, M. and Prasanthi, M. and Kumar, N. and Yedukondalu, N. and Rajput, N. K. and Saranya, P. S. and Narang, P. and Dutta, Prantu and Krishnan, R.} } @article {45480, title = {Synthesis, characterization, pharmacological and computational studies of 4, 5, 6, 7-tetrahydro-1, 3-benzothiazole incorporated azo dyes}, journal = {Journal of Molecular Structure}, volume = {1179}, year = {2019}, month = {MAR}, pages = {630-641}, type = {Article}, abstract = {

The present work describes the synthesis of five novel heterocyclic azo dyes (4a-4e) through conventional diazo-coupling reaction of 4, 5, 6, 7-tetrahydro-1, 3-benzothiazole with various coupling compounds at 0-5 degrees C. The chemical structures of the synthesized azo dyes were characterized by both theoretical and experimental techniques. All the synthesized molecules were evaluated for their antioxidant activity by two different techniques such as DPPH and FRAP. The results indicated that all the synthesized compounds proved to be potent antioxidants. The anti-mycobacterial activity of the azo dyes was tested against M. tuberculosis and the compounds 4a and 4e showed higher activity among the tested dyes. The DNA binding studies showed effective intercalation properties between the azo dyes and CT-DNA. Finally, the molecular docking studies indicated a possible interaction of the azo dyes with target receptor RpsA. (C) 2018 Elsevier B.V. All rights reserved.

}, keywords = {Azo dyes, Benzothiazole, CT-DNA, DFT, tuberculosis}, issn = {0022-2860}, doi = {10.1016/j.molstruc.2018.11.041}, author = {Maliyappa, M. R. and Keshavayya, J. and Mallikarjuna, N. M. and Krishna, P. Murali and Shivakumara, N. and Sandeep, Telkar and Sailaja, Krishnamurty and Nazrulla, Mohammed Azeezulla} } @article {46985, title = {Pharmacophore modeling of pretomanid (PA-824) derivatives for antitubercular potency against replicating and non-replicating Mycobacterium tuberculosis}, journal = {Journal of Biomolecular Structure \& Dynamics}, volume = {39}, year = {2021}, month = {FEB}, pages = {889-900}, type = {Article}, abstract = {

Pretomanid (PA-824) is the recently (2019) approved drug for the treatment of extensively drug-resistant (XDR) TB and the multidrug-resistant (MDR) TB by US FDA. The experimental data of antitubercular activity of 543 pretomanid derivatives (total 6 datasets) against replicating (active) and non-replicating (dormant) forms of Mycobacterium tuberculosis (strain H37Rv) are available in the literature. Such vast experimental data of pretomanid derivatives against both of these endpoints, and recent approval of pretomanid molecule as a drug encouraged us to utilize this existing experimental information for the development of the 3D-pharmacophore models. The developed model (Hypo-1, MABA) showed the three physicochemical features namely, the oxygen atom of nitro group (HBA_1), fused pyran ring of imidazopyran heterocycle (HYAl_2) and the 4-fluorophenyl moiety (HYAr_3) are crucial for the antitubercular activity against replicating M. tb. Subsequently, the pharmacophore model (Hypo-1, LORA) developed against the non-replicating form of M. tb also showed the contribution of three physicochemical features namely, the 4-tri-fluoromethyl group (HYAl_2) and both the phenyl groups (HYAr_3, HYAr_4) of biaryl moiety in increasing the antitubercular activity. Both the pharmacophoric classifier models showed the classification accuracies of 82.98 and 74.42\% for the training set compounds, and 63.91 and 61.60\% for the test set compounds respectively, for labelling the compounds into higher and lower active classes. Both the models were also found to be retaining the higher active compounds in top 1.00\% of the total number of compounds (decoys and actives), after performing the decoy set screening. Communicated by Ramaswamy H. Sarma

}, keywords = {LORA assay, MABA assay, Mycobacterium tuberculosis, non-replicating M, pharmacophore modeling, pretomanid derivatives, replicating M, tuberculosis, virtual screening}, issn = {0739-1102}, doi = {10.1080/07391102.2020.1719205, Early Access Date = JAN 2020}, author = {Aher, Rahul Balasaheb and Sarkar, Dhiman} } @article {48235, title = {Kupyaphores are zinc homeostatic metallophores required for colonization of Mycobacterium tuberculosis}, journal = {Proceedings of the National Academy of Sciences of the United States of America}, volume = {119}, year = {2022}, month = {FEB}, pages = {e2110293119}, type = {Article}, abstract = {

Mycobacterium tuberculosis (Mtb) endures a combination of metal scarcity and toxicity throughout the human infection cycle, contributing to complex clinical manifestations. Pathogens counteract this paradoxical dysmetallostasis by producing specialized metal trafficking systems. Capture of extracellular metal by siderophores is a widely accepted mode of iron acquisition, and Mtb iron-chelating siderophores, mycobactin, have been known since 1965. Currently, it is not known whether Mtb produces zinc scavenging molecules. Here, we characterize low-molecular-weight zinc-binding compounds secreted and imported by Mtb for zinc acquisition. These molecules, termed kupyaphores, are produced by a 10.8 kbp biosynthetic cluster and consists of a dipeptide core of ornithine and phenylalaninol, where amino groups are acylated with isonitrilecontaining fatty acyl chains. Kupyaphores are stringently regulated and support Mtb survival under both nutritional deprivation and intoxication conditions. A kupyaphore-deficient Mtb strain is unable to mobilize sufficient zinc and shows reduced fitness upon infection. We observed early induction of kupyaphores in Mtb-infected mice lungs after infection, and these metabolites disappeared after 2 wk. Furthermore, we identify an Mtb-encoded isonitrile hydratase, which can possibly mediate intracellular zinc release through covalent modification of the isonitrile group of kupyaphores. Mtb clinical strains also produce kupyaphores during early passages. Our study thus uncovers a previously unknown zinc acquisition strategy of Mtb that could modulate host-pathogen interactions and disease outcome.

}, keywords = {metallophore, nutritional immunity, tuberculosis, zinc}, issn = {0027-8424}, doi = {10.1073/pnas.2110293119}, author = {Mehdiratta, Kritee and Singh, Shubham and Sharma, Sachin and Bhosale, Rashmi S. and Choudhury, Rahul and Masal, Dattatraya P. and Manocha, Alzu and Dhamale, Bhushan Dilip and Khan, Naseem and Asokachandran, Vivekanand and Sharma, Pooja and Ikeh, Melanie and Brown, Amanda C. and Parish, Tanya and Ojha, Anil K. and Michael, Joy Sarojini and Faruq, Mohammed and Medigeshi, Guruprasad R. and Mohanty, Debasisa and Reddy, D. Srinivasa and Natarajan, Vivek T. and Kamat, Siddhesh S. and Gokhale, Rajesh S.} } @article {47820, title = {Probes and techniques used in active and the hypoxia-based dormant state of an antitubercular drug screening assay}, journal = {Medicine in Drug Discovery}, volume = {13}, year = {2022}, month = {MAR}, pages = {100115}, type = {Article}, abstract = {Current antitubercular drug therapy requires more than six months and is unable to kill latent or dormant forms of tuberculosis. Thus, it is a need of new drug therapy to fight against dormant tuberculosis. However, the major obstacle in the development of novel drugs for dormant tuberculosis is the lack of relevant screening systems and using reliable probes to measure growth inhibition. Until now, several probes used in active state assays are significantly determining the inhibitory effect against the active state of mycobacteria. The dormant condition assays are based on hypoxia-derived dormancy which include resazurin reduction assay, nitrite reductase assay, XTT reduction menadione assay and low oxygen recovery assay. Major probes used in those assays are colorimetric/fluorescent dyes, enzymatic activity, and reporter genes include luciferase and fluorescent proteins. Although these dormant assays are based on hypoxia-induced features and difficult to maintain for a longer duration. Also, they further complicated by growth detection and pursuit of high throughput screening criteria. Here we reviewed complications of probes and assay techniques used for anti-dormant drug screening programs of tuberculosis. This will provide the knowledge to design better alternative drug screening method for the anti-dormant form of tuberculosis.}, keywords = {Active and dormant states, and, Drug screening assay, Probes, tuberculosis}, issn = {2590-0986}, doi = {10.1016/j.medidd.2021.100115}, author = {Yeware, Amar and Akhtar, Shamim and Sarkar, Dhiman} } @article {48826, title = {Synthesis, biological evaluation and docking studies of silicon incorporated diarylpyrroles as MmpL3 inhibitors: an effective strategy towards development of potent anti-tubercular agents}, journal = {European Journal of Medicinal Chemistry}, volume = {259}, year = {2023}, month = {NOV }, pages = {115633}, type = {Article}, abstract = {

Growing global demand for new molecules to treat tuberculosis has created an urgent need to develop novel strategies to combat the menace. BM212 related compounds were found to be potent anti-TB agents and they inhibit mycolic acid transporter, MmpL3, a known potent drug target from Mycobacterium tuberculosis. In order to enhance their inhibitory potency, several silicon analogues of diarylpyrroles related to BM212 were designed, synthesized, and evaluated for anti-tubercular activities. In Alamar blue assay, most of the silicon-incorporated compounds were found to be more potent than the parent compound (BM212), against Mycobacterium tuberculosis (MIC = 1.7 \& mu;M, H37Rv). Docking results from the crystal structure of MmpL3 and silicon analogues as pharmacophore model also strongly correlate with the biological assays and suggest that the incorporation of silicon in the inhibitor scaffold could enhance their potency by stabilizing the hydrophobic residues at the binding pocket. The best docking hit, compound 12 showed an MIC of 0.1 \& mu;M against H37Rv with an acceptable in vitro ADME profile and excellent selectivity index. Overall, the present study indicates that, the designed silicon analogues, especially compound 12 could be a good inhibitor for an intrinsically flexible drug-binding pocket of MmpL3 and has potential for further development as anti-tubercular agents.

}, keywords = {antibiotic, BM212, docking studies, MmpL3 inhibitor, Silicon analogue, tuberculosis}, issn = {0223-5234}, doi = {10.1016/j.ejmech.2023.115633}, author = {Vasudevan, N. and Motiwala, Zenia and Ramesh, Remya and Wagh, Sachin B. and Shingare, Rahul D. and Katte, Revansiddha and Anand, Amitesh and Choudhary, Sushil and Kumar, Ajay and Gokhale, Rajesh S. and Kulkarni, Kiran A. and Reddy, D. Srinivasa} }