Project description:Investigation of whole genome gene expression level changes in Mycobacterium tuberculosis treated with the DHFR inhibitor WR99210, compared to untreated cells. The antimycobacterial properties of WR99210 are further described in Gerum, A., Ulmer, J., Jacobus, D., Jensen, N., Sherman, D., and C. Sibley. 2002. Novel Saccharomyces cerevisiae screen identifies WR99210 analogues that inhibit Mycobacterium tuberculosis dihydrofolate reductase. Antimicrob Agents Chemother 46(11):3362-3369 [PMID:12384337]
Project description:Drug susceptible Mycobacterium smegmatis (Mc2-155) was exposed to a sub-MIC concentration of antimycobacterial drug Rifampicin (treated) or DMSO (control). Cells were harvested at 30, 255 and 300 minutes post-exposure and the proteome at each time analysed using LC-MS/MS on a Thermo Q-Exactive.
Project description:Drug susceptible Mycobacterium smegmatis (Mc2-155) was exposed to a sub-MIC concentration of antimycobacterial drug Rifampicin (treated) or DMSO (control). Cells were harvested at 30, 255 and 300 minutes post-exposure and the proteome at each time analysed using LC-MS/MS on a Thermo Q-Exactive.
Project description:Investigation of whole genome gene expression level changes in Mycobacterium tuberculosis treated with the DHFR inhibitor WR99210, compared to untreated cells. The antimycobacterial properties of WR99210 are further described in Gerum, A., Ulmer, J., Jacobus, D., Jensen, N., Sherman, D., and C. Sibley. 2002. Novel Saccharomyces cerevisiae screen identifies WR99210 analogues that inhibit Mycobacterium tuberculosis dihydrofolate reductase. Antimicrob Agents Chemother 46(11):3362-3369 [PMID:12384337] A nine chip experiment in which total RNA was collected from H37Rv after treatment with 100 uM WR99210 for 0, 4, and 24 hours. Three separate cultures/biological replicates were interrogated for both treated and untreated cultures. Labeled cDNA was hybridized to NimbleGen spotted oligo tiling arrays covering both strands of the M. tuberculosis genome at ~200 bp intervals between 60-mer probes.
Project description:Non-tuberculous mycobacteria (NTM) are emerging pathogens with high intrinsic drug resistance. Among rapidly growing NTM species, Mycobacterium abscessus is among the most pathogenic. Standard of care therapy has led to unacceptable outcomes and demonstrates the urgent need to develop effective, broad-spectrum antimycobacterial regimens. Through synthetic modification of spectinomycin (SPC), an aminocyclitol antibiotic, we have identified a distinct structural subclass of ethylene linked aminomethyl spectinomycins (eAmSPC) that are up to 64-fold more potent against M. abscessus when compared to SPC. Lead eAmSPC retain activity against other NTM species and multi-drug resistant M. abscessus clinical isolates. Sequencing of eAmSPC-resistant mutants revealed nucleotide changes in the distinct helix-34 spectinomycin binding site and X-ray crystallography further demonstrated the derivatives mode of ribosomal inhibition remained on target. The eAmSPC displayed increased intracellular accumulation compared to SPC and transcriptional profiling indicate that eAmSPC’s induce whiB7 resistance responses, however, the series maintains potency despite its expression. These leads display favorable pharmacokinetic profiles and robust efficacy in M. abscessus mouse infection models. The results of these studies suggest that eAmSPCs have the potential to be developed into clinical treatments for M. abscessus and other NTM infections.
Project description:We used DNA microarrays to detect differentially expresses genes in a spontaneous mutant of Mycobacterium tuberculosis H37Rv resistant to azoles. We identified three adjacent upregulated genes encoding a transcription regulatory protein and two membrane proteins belonging to the family of RND efflux transporters.
Project description:The global burden of tuberculosis (TB) is aggravated by the continuously increasing emergence of drug resistance, highlighting the need for innovative therapeutic options. The concept of host-directed therapy (HDT) as adjunctive to classical antibacterial therapy with antibiotics represents a novel and promising approach for treating TB. Here, we have focused on repurposing the clinically used anticancer drug tamoxifen, which was identified as a molecule with strong host-directed activity against intracellular Mycobacterium tuberculosis (Mtb). Using a primary human macrophage Mtb infection model, we demonstrate the potential of tamoxifen against drug-sensitive as well as drug-resistant Mtb bacteria. The therapeutic effect of tamoxifen was confirmed in an in vivo TB model based on Mycobacterium marinum infection of zebrafish larvae. Tamoxifen had no direct antimicrobial effects at the concentrations used, confirming that tamoxifen acted as an HDT drug. Furthermore, we demonstrate that the antimycobacterial effect of tamoxifen is independent of its well-known target the estrogen receptor (ER) pathway, but instead acts by modulating autophagy, in particular the lysosomal pathway. Through RNA sequencing and microscopic colocalization studies, we show that tamoxifen stimulates lysosomal activation and increases the localization of mycobacteria in lysosomes both in vitro and in vivo, while inhibition of lysosomal activity during tamoxifen treatment partly restores mycobacterial survival. Thus, our work highlights the HDT potential of tamoxifen and proposes it as a repurposed molecule for the treatment of TB.
Project description:11 Mycobacterium tuberculosis mutants resistant to D-cycloserine were isolated in the laboratory. Genomic DNA was isolated and whole genomes were sequenced to perform SNP calling and identify possible mutations associated with resistance.