Project description:The new microarray described for Mycobacterium tuberculosis in our study has a more complete reprensentation of the genome than any other array design reported till date. Further, protocols for sample preparation, labelling and hybridisation for accurate gene expression profiling of M.tuberculosis have been optimised. Whole genome expression profiling on Mycobacterium tuberculosis H37Rv (OD600 0.4-0.5) was performed using exponential phase cultures after 0 and 6 Hrs in presence and absence of drug (Isoniazid) by using PolyA-dT and WT method. The exponential culture after 24 and 72 Hrs were used for validating the specific hybridization with or without formamide. All time points had two biological replicates with two technical replicates.
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:The new microarray described for Mycobacterium tuberculosis in our study has a more complete reprensentation of the genome than any other array design reported till date. Further, protocols for sample preparation, labelling and hybridisation for accurate gene expression profiling of M.tuberculosis have been optimised.
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:Currently available model organisms such as Mycobacterium smegmatis and Mycobacterium bovis Bacillus Calmette-Guérin (BCG) have significantly contributed to our understanding of tuberculosis (TB) biology, these models have limitations such as differences in genome size, growth rates and virulence. Attenuated Mycobacterium tuberculosis strains may provide more representative, safer models to study M. tuberculosis biology. For example, the M. tuberculosis ΔleuDΔpanCD double auxotroph, has undergone rigorous in vitro and in vivo safety testing. Like other auxotrophic strains, this has subsequently been approved for use in biosafety level (BSL) 2 facilities. Auxotrophic strains have been assessed as models for drug-resistant M. tuberculosis and for studying latent TB. These offer the potential as safe and useful models, but it is important to understand how well these recapitulate salient features of non-attenuated M. tuberculosis. We therefore performed a comprehensive comparison of M. tuberculosis H37Rv and M. tuberculosis ΔleuDΔpanCD. These strains demonstrated similar in vitro and intra-macrophage replication rates, similar responses to anti-TB agents and whole genome sequence conservation. Shotgun proteomics analysis suggested that M. tuberculosis ΔleuDΔpanCD has an increased propensity to enter a dormant state during acid stress, which has been verified using a dual-fluorescent replication reporter assay. Importantly, infection of human peripheral blood mononuclear cells with the 2 strains elicited comparable cytokine production, demonstrating the suitability of M. tuberculosis ΔleuDΔpanCD for immunological assays. We provide comprehensive evidence to support the judicious use of M. tuberculosis ΔleuDΔpanCD as a safe and suitable model organism for M. tuberculosis research, without the need for a BSL3 facility.
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:In other bacteria, arginine induces the expression of genes involved in arginine catabolism. This study obtained the identification of genes involved in the arginine metabolism of Mycobacterium tuberculosis. Mycobacterium tuberculosis was cultured with arginine or ammonium chloride as sole nitrogen source. In the log phase of growth, RNA was isolated and whole genome expression was determined. The study contains three biological replicates.
Project description:Comparison of gene expression profile of the whiB4 mutant strain of Mycobacterium tuberculosis with the wild type Mycobacterium tuberculosis H37RV Mtb WhiB4 mutant mRNA was compared with the mRNA of wtMtb H37RV under aerobic conditons