Project description:We analyzed the genes expressed, or the transcriptome, of bacilli (Mycobacterium tuberculosis) growing in fatty acids as sole carbon source. Using new technologies to massively sequence of RNA molecules we identified a group of genes that provides novel insight regarding the metabolic pathways and transcriptional regulation of latent M. Tuberculosis.
Project description:A comparative genomic approach was used to identify large sequence polymorphisms among Mycobacterium avium isolates obtained from a variety of host species. DNA microarrays were used as a platform for comparing mycobacteria field isolates with the sequenced bovine isolate Mycobacterium avium subsp. paratuberculosis (Map) K10. ORFs were classified as present or divergent based on the relative fluorescent intensities of the experimental samples compared to Map K10 DNA. Map isolates cultured from cattle, bison, sheep, goat, avian, and human sources were hybridized to the Map microarray. Three large deletions were observed in the genomes of four Map isolates obtained from sheep and four clusters of ORFs homologous to sequences in the Mycobacterium avium subsp. avium (Maa) 104 genome were identified as being present in these isolates. One of these clusters encodes glycopeptidolipid biosynthesis enzymes. One of the Map sheep isolates had a genome profile similar to a group of Mycobacterium avium subsp. silvaticum (Mas) isolates which included four independent laboratory stocks of the organism traditionally identified as Maa strain 18. Genome diversity in Map appears to be mostly restricted to large sequence polymorphisms that are often associated with mobile genetic elements. Keywords: Comparative genomic hybridization
Project description:Related surrogate species are often used to study the molecular basis of pathogenicity of a pathogen on the basis of a shared set of biological features generally attributable to a shared core genome consisting of orthologous genes. An important and understudied aspect, however, is the extent to which regulatory features affecting the expression of such shared genes are present in both species. Here we report on an analysis of whole transcriptome maps for an important member of the TB complex Mycobacterium bovis and a closely related model organism for studying mycobacterial pathogenicity Mycobacterium marinum.
Project description:We analyzed the genes expressed, or the transcriptome, of bacilli (Mycobacterium tuberculosis) growing in fatty acids as sole carbon source. Using new technologies to massively sequence of RNA molecules we identified a group of genes that provides novel insight regarding the metabolic pathways and transcriptional regulation of latent M. Tuberculosis. Comparative Transcriptomics between two carbon source (Dextrose, Long Fatty Acids), at two states of growth (Exponential and Stationary Phase)
Project description:We employed a proteogenomics workflow to identify microproteins encoded by small Open Reading Frames (ORFs) in the genome of Mycobacterium smegmatis strain mc²155.
Project description:Related surrogate species are often used to study the molecular basis of pathogenicity of a pathogen on the basis of a shared set of biological features generally attributable to a shared core genome consisting of orthologous genes. An important and understudied aspect, however, is the extent to which regulatory features affecting the expression of such shared genes are present in both species. Here we report on an analysis of whole transcriptome maps for an important member of the TB complex Mycobacterium bovis and a closely related model organism for studying mycobacterial pathogenicity Mycobacterium marinum. Predict transcription start site
Project description:A comparative genomic approach was used to identify large sequence polymorphisms among Mycobacterium avium isolates obtained from a variety of host species. DNA microarrays were used as a platform for comparing mycobacteria field isolates with the sequenced bovine isolate Mycobacterium avium subsp. paratuberculosis (Map) K10. ORFs were classified as present or divergent based on the relative fluorescent intensities of the experimental samples compared to Map K10 DNA. Map isolates cultured from cattle, bison, sheep, goat, avian, and human sources were hybridized to the Map microarray. Three large deletions were observed in the genomes of four Map isolates obtained from sheep and four clusters of ORFs homologous to sequences in the Mycobacterium avium subsp. avium (Maa) 104 genome were identified as being present in these isolates. One of these clusters encodes glycopeptidolipid biosynthesis enzymes. One of the Map sheep isolates had a genome profile similar to a group of Mycobacterium avium subsp. silvaticum (Mas) isolates which included four independent laboratory stocks of the organism traditionally identified as Maa strain 18. Genome diversity in Map appears to be mostly restricted to large sequence polymorphisms that are often associated with mobile genetic elements. Keywords: Comparative genomic hybridization Each isolate was competitively hybridized against Map K10 with a minimum of 2 dye flip hybridizations per isolate.
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.