Project description:A cell-based phenotypic screen for inhibitors of biofilm formation in Mycobacterium tuberculosis (Mtb) identified the small molecule TCA1, which has bactericidal activity against both drug susceptible and drug resistant Mtb, and synergizes with rifampicin (RIF) or isoniazid (INH) in sterilization of Mtb in vitro. In addition, TCA1 has bactericidal activity against non-replicating Mtb in vitro and is efficacious in acute and chronic Mtb infection mouse models, both alone and in combination with INH or RIF. Transcriptional analysis revealed that TCA1 down-regulates genes known to be involved in Mtb dormancy and drug tolerance. Mutagenesis and affinity-based methods identified DprE1 and MoeW, enzymes involved in cell wall and molybdenum cofactor biosynthesis, respectively, as the targets responsible for TCA1’s activity. These in vitro and in vivo results indicate that TCA1functions by a novel mechanism and suggest that it may be the first product of a promising new approach for the development of anti-tuberculosis drugs.
Project description:A cell-based phenotypic screen for inhibitors of biofilm formation in Mycobacterium tuberculosis (Mtb) identified the small molecule TCA1, which has bactericidal activity against both drug susceptible and drug resistant Mtb, and synergizes with rifampicin (RIF) or isoniazid (INH) in sterilization of Mtb in vitro. In addition, TCA1 has bactericidal activity against non-replicating Mtb in vitro and is efficacious in acute and chronic Mtb infection mouse models, both alone and in combination with INH or RIF. Transcriptional analysis revealed that TCA1 down-regulates genes known to be involved in Mtb dormancy and drug tolerance. Mutagenesis and affinity-based methods identified DprE1 and MoeW, enzymes involved in cell wall and molybdenum cofactor biosynthesis, respectively, as the targets responsible for TCA1M-bM-^@M-^Ys activity. These in vitro and in vivo results indicate that TCA1functions by a novel mechanism and suggest that it may be the first product of a promising new approach for the development of anti-tuberculosis drugs. Transcriptional profile of TCA1-treated cells relative to DMSO-treated control. Three biological replicates, third is a dye flip.
Project description:Human peripheral blood mononuclear cells were cultured in presence of H37Ra strain at 37oC, 5%CO2. Cellular aggregates were collected at 24h, and RNA extracted and hybridized to Affymetrix microarrays (HG-U133). Raw data from microarray experiments was analyzed with dCHIP and SAM programs to determine the significance of changes at the biological context.
Project description:The emergence of drug resistance among tuberculosis (TB) patients is often associated with their non-compliance to the length of the chemotherapy, which can reach up to 2 years for the treatment of multi-drug-resistant (MDR) TB. Drugs that would kill TB faster and would not lead to the development of drug resistance could shorten chemotherapy significantly. In Escherichia coli, the common mechanism of cell death by bactericidal antibiotics is the generation of highly reactive hydroxyl radicals via the Fenton reaction. Since ascorbic acid (vitamin C) is known to drive the Fenton reaction, we tested whether the Fenton reaction could lead to a bactericidal event in Mycobacterium tuberculosis by treating M. tuberculosis cultures with vitamin C. Here, we report that the addition of vitamin C to drug-susceptible, MDR and extensively drug-resistant (XDR) M. tuberculosis strains results in sterilization of the cultures in vitro. We show that the sterilizing effect of vitamin C on M. tuberculosis was dependent on the production of high ferrous ion levels and reactive oxygen species. Although, this potent sterilizing activity of vitamin C against M. tuberculosis in vitro was not observed in mice, we believe this activity needs further investigation.
Project description:The global diversity of Mycobacterium tuberculosis comprises at least seven lineages, each with its distinct geographic distribution. The aim of this experiment was to perform a comparative analysis of two of these lineages: Lineage 1 and Lineage 2. The former is found around the rim of the Indian ocean and in south-east Asia, while the latter is widely spread throughout Asia and shows an increasing global spread. We have chosen three fully drug susceptible clincal isolates to represent each of the two lineages. We performed RNAseq analysis on rRNA depleted samples isolated from cultures during mid-log phase. Each strain was measured in triplicate.
Project description:The emergence of drug resistance among tuberculosis (TB) patients is often associated with their non-compliance to the length of the chemotherapy, which can reach up to 2 years for the treatment of multi-drug-resistant (MDR) TB. Drugs that would kill TB faster and would not lead to the development of drug resistance could shorten chemotherapy significantly. In Escherichia coli, the common mechanism of cell death by bactericidal antibiotics is the generation of highly reactive hydroxyl radicals via the Fenton reaction. Since ascorbic acid (vitamin C) is known to drive the Fenton reaction, we tested whether the Fenton reaction could lead to a bactericidal event in Mycobacterium tuberculosis by treating M. tuberculosis cultures with vitamin C. Here, we report that the addition of vitamin C to drug-susceptible, MDR and extensively drug-resistant (XDR) M. tuberculosis strains results in sterilization of the cultures in vitro. We show that the sterilizing effect of vitamin C on M. tuberculosis was dependent on the production of high ferrous ion levels and reactive oxygen species. Although, this potent sterilizing activity of vitamin C against M. tuberculosis in vitro was not observed in mice, we believe this activity needs further investigation. Comparison of vitamin C treated Mycobacterium tuberculosis transcriptome relative to untreated; Three biological replicates, second is a dye flip
Project description:Tuberculosis (TB) is one of the deadliest infectious disorders in the world. To effectively TB manage, an essential step is to gain insight into the lineage of Mycobacterium tuberculosis (MTB) strains and the distribution of drug resistance. Although the Campania region is declared a cluster area for the infection, to contribute to the effort to understand TB evolution and transmission, still poorly known, we have generated a dataset of 159 genomes of MTB strains, from Campania region collected during 2018-2021, obtained from the analysis of whole genome sequence data. The results show that the most frequent MTB lineage is the 4 according for 129 strains (81.11%). Regarding drug resistance, 139 strains (87.4%) were classified as multi susceptible, while the remaining 20 (12.58%) showed drug resistance. Among the drug-resistance strains, 8 were isoniazid-resistant MTB (HR-MTB), 7 were resistant only to one antibiotic (3 were resistant only to ethambutol and 3 isolate to streptomycin while one isolate showed resistance to fluoroquinolones), 4 multidrug-resistant MTB, while only one was classified as pre-extensively drug-resistant MTB (pre-XDR). This dataset expands the existing available knowledge on drug resistance and evolution of MTB, contributing to further TB-related genomics studies to improve the management of TB infection.