title: The transcriptional responses of Mycobacterium tuberculosis to inhibitors of metabolism: novel insights into drug mechanisms of action.
abstract: The differential transcriptional response of Mycobacterium tuberculosis to drugs and growth-inhibitory conditions was monitored to generate a data set of 430 microarray profiles. Unbiased grouping of these profiles independently clustered agents of known mechanism of action accurately and was successful at predicting the mechanism of action of several unknown agents. These predictions were validated biochemically for two agents of previously uncategorized mechanism, pyridoacridones and phenothiazines. Analysis of this data set further revealed 150 underlying clusters of coordinately regulated genes offering the first glimpse at the full metabolic potential of this organism. A signature subset of these gene clusters was sufficient to classify all known agents as to mechanism of action. Transcriptional profiling of both crude and purified natural products can provide critical information on both mechanism and detoxification prior to purification that can be used to guide the drug discovery process. Thus, the transcriptional profile generated by a crude marine natural product recapitulated the mechanistic prediction from the pure active component. The underlying gene clusters further provide fundamental insights into the metabolic response of bacteria to drug-induced stress and provide a rational basis for the selection of critical metabolic targets for screening for new agents with improved activity against this important human pathogen.
authors.affiliation: Tuberculosis Research Section, NIAID, National Institutes of Health, Rockville, Maryland 20852, USA. HBOSHOFF@niaid.nih.gov
authors.forename: Helena I M
authors.initials: HI
authors.lastname: Boshoff
authors.forename: Timothy G
authors.initials: TG
authors.lastname: Myers
authors.forename: Brent R
authors.initials: BR
authors.lastname: Copp
authors.forename: Michael R
authors.initials: MR
authors.lastname: McNeil
authors.forename: Michael A
authors.initials: MA
authors.lastname: Wilson
authors.forename: Clifton E
authors.initials: CE
authors.lastname: Barry
mesh_terms: D014150:Antipsychotic Agents / Q000494:pharmacology; D000995:Antitubercular Agents / Q000494:pharmacology; D001393:Azoles / Q000494:pharmacology; D002473:Cell Wall / Q000187:drug effects / Q000378:metabolism; D027081:DNA Gyrase / Q000378:metabolism; D015195:Drug Design; D004579:Electron Transport / Q000187:drug effects; D004734:Energy Metabolism / Q000187:drug effects*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D004977:Ethambutol / Q000494:pharmacology; D024841:Fluoroquinolones / Q000494:pharmacology; D015964:Gene Expression Regulation, Bacterial / Q000187:drug effects* / Q000502:physiology; D016680:Genome, Bacterial; D009169:Mycobacterium tuberculosis / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism*; D020411:Oligonucleotide Array Sequence Analysis; D010640:Phenothiazines / Q000494:pharmacology; D059005:Topoisomerase II Inhibitors; D015533:Transcriptional Activation / Q000187:drug effects
chemical_list: D014150:Antipsychotic Agents; D000995:Antitubercular Agents; D001393:Azoles; D004791:Enzyme Inhibitors; D024841:Fluoroquinolones; D010640:Phenothiazines; D059005:Topoisomerase II Inhibitors; D004977:Ethambutol; D027081:DNA Gyrase