01275nas a2200253 4500008004100000022001400041245006000055210006000115260009500175300001200270490000800282520047900290653001200769653001200781653001700793653001800810653001600828653001100844100001900855700001800874700002100892700001900913856008900932 2011 eng d a0003-269700aMethod to extract intact and pure RNA from mycobacteria0 aMethod to extract intact and pure RNA from mycobacteria a525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USAbACADEMIC PRESS INC ELSEVIER SCIENCEcOCT a286-2880 v4173 a

We describe a high-yielding, simple, and aerosol-free protocol for the isolation of RNA from mycobacteria that does not require sophisticated instruments. The method yielded 50 mu g of RNA from 10(7) cells, 50 times more than a recently reported method. Our method can extract total RNA from aerobically grown bacteria and from in vitro hypoxia-induced dormant bacilli and mycobacteria residing within infected macrophages. (C) 2011 Elsevier Inc. All rights reserved.

10aDormant10aHypoxia10aMycobacteria10aRNA isolation10aSpheroplast10aTrizol1 aAkhtar, Shamim1 aSarkar, Sampa1 aMishra, Abhishek1 aSarkar, Dhiman uhttps://library.ncl.res.in/content/method-extract-intact-and-pure-rna-mycobacteria-002356nas a2200289 4500008004100000022001400041245009700055210006900152260007300221300001200294490000700306520133900313653002601652653002801678653001701706653001701723653001801740653001701758100001701775700002301792700002401815700002901839700002501868700001901893700002601912856012801938 2015 eng d a0924-857900aChemical and biological metal nanoparticles as antimycobacterial agents: a comparative study0 aChemical and biological metal nanoparticles as antimycobacterial aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcAUG a183-1880 v463 a

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.

10aAntibiotic resistance10aAntimycobacterial agent10aCytotoxicity10aMycobacteria10aNanoparticles10atuberculosis1 aSingh, Richa1 aNawale, Laxman, U.1 aArkile, Manisha, A.1 aShedbalkar, Utkarsha, U.1 aWadhwani, Sweety, A.1 aSarkar, Dhiman1 aChopade, Balu, Ananda uhttps://library.ncl.res.in/content/chemical-and-biological-metal-nanoparticles-antimycobacterial-agents-comparative-study-003131nas a2200301 4500008004100000022001400041245008900055210006900144260008400213300001600297490000700313520210200320653002802422653001702450653002002467653001702487653001802504653001702522100001702539700001902556700002402575700002102599700002502620700002002645700001902665700002602684856011902710 2016 eng d a1178-201300aPhytogenic silver, gold, and bimetallic nanoparticles as novel antitubercular agents0 aPhytogenic silver gold and bimetallic nanoparticles as novel ant aPO BOX 300-008, ALBANY, AUCKLAND 0752, NEW ZEALANDbDOVE MEDICAL PRESS LTDcMAY a1889—18970 v113 a

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.

10aAntimycobacterial agent10aCytotoxicity10adrug resistance10aMycobacteria10aNanoparticles10atuberculosis1 aSingh, Richa1 aNawale, Laxman1 aArkile, Manisha, A.1 aWadhwani, Sweety1 aShedbalkar, Utkarsha1 aChopade, Snehal1 aSarkar, Dhiman1 aChopade, Balu, Ananda uhttps://library.ncl.res.in/content/phytogenic-silver-gold-and-bimetallic-nanoparticles-novel-antitubercular-agents02545nas a2200277 4500008004100000022001400041245012300055210006900178260000800247300001100255490000800266520161900274653001301893653002601906653001401932653001601946653001901962653001701981653003101998100002102029700002702050700002202077700002402099700001802123856012602141 2021 eng d a0882-401000aPNA-mediated efflux inhibition as a therapeutic strategy towards overcoming drug resistance in Mycobacterium smegmatis0 aPNAmediated efflux inhibition as a therapeutic strategy towards  cFEB a1047370 v1513 a

The emergence of antibiotic-resistant strains of Mycobacterium tuberculosis and the decelerating development of new and effective antibiotics has impaired the treatment of tuberculosis (TB). Efflux pump inhibitors (EPIs) have the potential to improve the efficacy of existing anti-TB drugs although with toxicity limitations. Peptide nucleic acids (PNAs), oligonucleotide mimics, by virtue of their high nucleic acid binding specificity have the capability to overcome this drawback. We, therefore, investigated the efflux pump inhibitory properties of a PNA designed against an efflux pump of Mycobacterium smegmatis. LfrA, an efflux pump found in M. smegmatis, is majorly involved in conferring innate drug resistance to this strain and, therefore, was selected as a target for gene silencing via PNA. qRT-PCR and EtBr assays confirmed the EPI activity of the anti-lfrA PNA. On testing the effect of the anti-lfrA PNA on the bactericidal activity of a fluoroquinolone, norfloxacin, we observed that 5 mu M of anti-lfrA PNA in combination with norfloxacin led to an enhanced killing of up to 2.5 log-fold against wild-type and a lab-generated multidrug resistant strain, exemplifying its potential in countering resistance. Improved efficacy was also observed against intra-macrophage mycobacteria, where the drug-PNA combination enhanced bacterial clearance by 1.3 log-fold. Further, no toxicity was observed with PNA concentrations up to 4 times higher than the efficacious anti-lfrA PNA concentration. Thus, PNA, as an adjuvant, presents a novel and viable approach to rejuvenate anti-TB therapeutics.

10aAdjuvant10aAntibiotic resistance10aAntisense10aEfflux pump10aGene silencing10aMycobacteria10aPeptide nucleic acid (PNA)1 aGhosh, Saptarshi1 aCotta, Karishma, Berta1 aHande, Aniket, A.1 aFernandes, Moneesha1 aMehra, Sarika uhttps://library.ncl.res.in/content/pna-mediated-efflux-inhibition-therapeutic-strategy-towards-overcoming-drug-resistance