Publications by authors named "Ana Luisa De Jesus Lopes Ribeiro"

Mycobacterium tuberculosis, the etiological agent of the infectious disease tuberculosis, kills approximately 1.5 million people annually, while the spread of multidrug-resistant strains is of great global concern. Thus, continuous efforts to identify new antitubercular drugs as well as novel targets are crucial.

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To combat the emergence of drug-resistant strains of Mycobacterium tuberculosis, new antitubercular agents and novel drug targets are needed. Phenotypic screening of a library of 594 hit compounds uncovered two leads that were active against M. tuberculosis in its replicating, non-replicating, and intracellular states: compounds 7947882 (5-methyl-N-(4-nitrophenyl)thiophene-2-carboxamide) and 7904688 (3-phenyl-N-[(4-piperidin-1-ylphenyl)carbamothioyl]propanamide).

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Phenotypic screening of a quinoxaline library against replicating Mycobacterium tuberculosis led to the identification of lead compound Ty38c (3-((4-methoxybenzyl)amino)-6-(trifluoromethyl)quinoxaline-2-carboxylic acid). With an MIC99 and MBC of 3.1 μM, Ty38c is bactericidal and active against intracellular bacteria.

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The emergence of multidrug- and extensively drug-resistant strains of Mycobacterium tuberculosis highlights the need to discover new antitubercular agents. Here we describe the synthesis and characterization of a new series of thienopyrimidine (TP) compounds that kill both replicating and non-replicating M. tuberculosis.

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We report here the discovery, synthesis and screening results of a series of 3-(9H-fluoren-9-yl)pyrrolidine-2,5-dione derivatives as a novel class of potent inhibitors of Mycobacterium tuberculosis H37Rv strain as well as the enoyl acyl carrier protein reductase (ENR) InhA. Among them, several compounds displayed good activities against InhA which is one of the key enzymes involved in the type II fatty acid biosynthesis pathway of the mycobacteria cell wall. Furthermore, some exhibited promising activities against M.

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Among the species of the Mycobacterium genus, more than 50 have been recognized as human pathogens. In spite of the different diseases caused by mycobacteria, the interspecies genetic similarity ranges from 94% to 100%, and for some species, this value is higher than in other bacteria. Consequently, it is important to understand the relationships existing among mycobacterial species.

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Two series of α-ketotriazole and α,β-diketotriazole derivatives were synthesized and evaluated for antitubercular and cytotoxic activities. Among them, two α,β-diketotriazole compounds, 6b and 9b, exhibited good activities (minimum inhibitory concentration = 7.6 μM and 6.

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Multidrug resistance is a major barrier in the battle against tuberculosis and still a leading cause of death worldwide. In order to fight this pathogen, two routes are practicable: vaccination or drug treatment. Vaccination against Mycobacterium tuberculosis with the current vaccine Mycobacterium bovis Bacillus Calmette-Guerin is partially successful, being its efficacy variable.

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Tuberculosis is still a leading cause of death worldwide. The selection and spread of Mycobacterium tuberculosis multidrug-resistant (MDR-TB) and extensively drug-resistant strains (XDR-TB) is a severe public health problem. Recently, two different classes of chemical series, the benzothiazinones (BTZ) and the dinitrobenzamide (DNB) derivatives have been found to be highly active against M.

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Efflux transporters have a considerable role in the multidrug resistance (MDR) of Pseudomonas aeruginosa, an important nosocomial pathogen. In this study, 45 P. aeruginosa clinical strains, with an MDR phenotype, have been isolated in a hospital of Northern Italy and characterized to identify the mechanisms responsible for their fluoroquinolone (FQ) resistance.

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Tuberculosis is still a leading cause of death in developing countries, for which there is an urgent need for new pharmacological agents. The synthesis of the novel antimycobacterial drug class of benzothiazinones (BTZs) and the identification of their cellular target as DprE1 (Rv3790), a component of the decaprenylphosphoryl-β-d-ribose 2'-epimerase complex, have been reported recently. Here, we describe the identification and characterization of a novel resistance mechanism to BTZ in Mycobacterium smegmatis.

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The new antitubercular drug candidate 2-[2-S-methyl-1,4-dioxa-8-azaspiro[4.5]dec-8-yl]-8-nitro-6-(trifluoromethyl)-4H-1,3-benzothiazin-4-one (BTZ043) targets the DprE1 (Rv3790) subunit of the enzyme decaprenylphosphoryl-beta-d-ribose 2'-epimerase. To monitor the potential development of benzothiazinone (BTZ) resistance, a total of 240 sensitive and multidrug-resistant Mycobacterium tuberculosis clinical isolates from four European hospitals were surveyed for the presence of mutations in the dprE1 gene and for BTZ susceptibility.

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Tuberculosis (TB) remains the leading cause of mortality due to a bacterial pathogen, Mycobacterium tuberculosis. Moreover, the recent isolation of M. tuberculosis strains resistant to both first- and second-line antitubercular drugs (XDR-TB) threatens to make the treatment of this disease extremely difficult and becoming a threat to public health worldwide.

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