Details
- Autor(en) / Beteiligte
- Titel
- A Mycobacterium tuberculosis sigma factor network responds to cell-envelope damage by the promising anti-mycobacterial thioridazine
- Ist Teil von
- PloS one, 2010-04, Vol.5 (4), p.e10069
- Ort / Verlag
- United States: Public Library of Science
- Erscheinungsjahr
- 2010
- Link zum Volltext
- Quelle
- MEDLINE
- Beschreibungen/Notizen
- Novel therapeutics are urgently needed to control tuberculosis (TB). Thioridazine (THZ) is a candidate for the therapy of multidrug and extensively drug-resistant TB. We studied the impact of THZ on Mycobacterium tuberculosis (Mtb) by analyzing gene expression profiles after treatment at the minimal inhibitory (1x MIC) or highly inhibitory (4x MIC) concentrations between 1-6 hours. THZ modulated the expression of genes encoding membrane proteins, efflux pumps, oxido-reductases and enzymes involved in fatty acid metabolism and aerobic respiration. The Rv3160c-Rv3161c operon, a multi-drug transporter and the Rv3614c/3615c/3616c regulon, were highly induced in response to THZ. A significantly high number of Mtb genes co-expressed with sigma(B) (the sigma(B) regulon) was turned on by THZ treatment. sigma(B) has recently been shown to protect Mtb from envelope-damage. We hypothesized that THZ damages the Mtb cell-envelope, turning on the expression of the sigma(B) regulon. Consistent with this hypothesis, we present electron-microscopy data which shows that THZ modulates cell-envelope integrity. Moreover, the Mtb mutants in sigma(H) and sigma(E), two alternate stress response sigma factors that induce the expression of sigma(B), exhibited higher sensitivity to THZ, indicating that the presence and expression of sigma(B) allows Mtb to resist the impact of THZ. Conditional induction of sigma(B) levels increased the survival of Mtb in the presence of THZ. THZ targets different pathways and can thus be used as a multi-target inhibitor itself as well as provide strategies for multi-target drug development for combination chemotherapy. Our results show that the Mtb sigma factor network comprising of sigma(H), sigma(E) and sigma(B) plays a crucial role in protecting the pathogen against cell-envelope damage.
- Sprache
- Englisch
- Identifikatoren
- ISSN: 1932-6203eISSN: 1932-6203DOI: 10.1371/journal.pone.0010069Titel-ID: cdi_plos_journals_1289449673
- Format
- –
- Schlagworte
- Aerobic respiration, Analysis, Anti-Bacterial Agents - pharmacology, Antibiotics, Bacteriology, Cell Wall - drug effects, Chemotherapy, Chromosomes, Combination drug therapy, Damage, Dose-Response Relationship, Drug, Drug development, Drug resistance, Drug resistance in microorganisms, Drug therapy, Combination, Efflux, Enzymes, Fatty acids, Gene expression, Gene Expression Profiling, Gene Expression Regulation - drug effects, Genes, Genes, Bacterial - drug effects, Genetic aspects, Infectious Diseases/Bacterial Infections, Kinetics, Membrane proteins, Metabolism, Microbial drug resistance, Microbiology/Cellular Microbiology and Pathogenesis, Microbiology/Microbial Evolution and Genomics, Microbiology/Microbial Physiology and Metabolism, Microscopy, Minimum inhibitory concentration, Mutants, Mycobacterium smegmatis, Mycobacterium tuberculosis, Mycobacterium tuberculosis - drug effects, Mycobacterium tuberculosis - genetics, Mycobacterium tuberculosis - ultrastructure, Parasitology, Phenothiazine, Phenothiazines, Phosphorylation, Physiological aspects, Proteins, Reductases, RNA polymerase, Sigma factor, Sigma Factor - genetics, Thioridazine, Thioridazine - pharmacology, Thioridazine - therapeutic use, Transcription factors, Tuberculosis