Environmental Response and Autoregulation of Clostridium difficile TxeR, a Sigma Factor for Toxin Gene Expression
| Autor: | Lisa Barroso, Pauline Howarth, Julian I. Rood, Tracy D. Wilkins, Nagraj Mani, Dena Lyras, Bruno Dupuy, Abraham L. Sonenshein |
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| Přispěvatelé: | Department of Molecular Biology and Microbiology [Tufts, Boston], Tufts University School of Medicine [Boston], Department of Microbiology [Monash University, Australia], School of Biomedical Sciences [Monash University, Clayton], Monash University [Clayton]-Monash University [Clayton], Fralin Biotechnology Center [Blacksburg], Virginia Tech [Blacksburg], Génétique Moléculaire Bactérienne, Institut Pasteur [Paris], This work was supported by a postdoctoral fellowship to N. Mani from the Charles A. King Trust, a research grant from the Public Health Service (GM42219) to A. L. Sonenshein, a grant from the Australian National Health and Medical Research Council to J. I. Rood, and funds from the Institut Pasteur (Paris)., We thank S. Cole for critical review of the manuscript, A. Kolb for the gift of E. coli σ70, D. Acheson for help in preparing antibody to TxeR, S. B. Melville for providing strain SM101, and S. Karlsson and colleagues for allowing us to cite their unpublished results., Institut Pasteur [Paris] (IP) |
| Rok vydání: | 2002 |
| Předmět: |
Transcriptional Activation
MESH: Transcriptional Activation Clostridium perfringens [SDV]Life Sciences [q-bio] Sigma Factor Environment Biology Microbiology MESH: Clostridium perfringens/genetics 03 medical and health sciences Plasmid Bacterial Proteins Sigma factor Transcription (biology) MESH: Sigma Factor/metabolism MESH: DNA-Directed RNA Polymerases/metabolism MESH: Promoter Regions Genetic Gene expression Escherichia coli Homeostasis [SDV.BBM]Life Sciences [q-bio]/Biochemistry Molecular Biology Promoter Regions Genetic MESH: Environment Molecular Biology Gene MESH: Clostridium perfringens/growth & development 030304 developmental biology Molecular Biology of Pathogens Regulation of gene expression 0303 health sciences Reporter gene Clostridioides difficile MESH: Escherichia coli 030306 microbiology MESH: Sigma Factor/genetics Promoter DNA-Directed RNA Polymerases Gene Expression Regulation Bacterial Molecular biology MESH: Homeostasis MESH: Clostridium difficile/genetics MESH: Bacterial Proteins/genetics MESH: Bacterial Proteins/metabolism MESH: Gene Expression Regulation Bacterial |
| Zdroj: | Journal of Bacteriology Journal of Bacteriology, American Society for Microbiology, 2002, 184 (21), pp.5971-5978. ⟨10.1128/jb.184.21.5971-5978.2002⟩ Monash University Journal of Bacteriology, 2002, 184 (21), pp.5971-5978. ⟨10.1128/jb.184.21.5971-5978.2002⟩ |
| ISSN: | 1098-5530 0021-9193 |
| Popis: | TxeR, a sigma factor that directs Clostridium difficile RNA polymerase to recognize the promoters of two major toxin genes, was shown to stimulate its own synthesis. Whether expressed in C. difficile , Clostridium perfringens , or Escherichia coli , TxeR stimulated transcription of fusions of the txeR promoter region to reporter genes. As is the case for the tox genes, txeR expression was responsive to the cellular growth phase and the constituents of the medium. That is, the level of expression in broth culture was low during the exponential growth phase, but rapidly increased as cells approached the stationary phase. In the presence of excess glucose, expression from the txeR promoter was repressed. The results support a model for toxin gene expression in which synthesis of TxeR is induced by specific environmental signals. The increased level of TxeR then permits high-level expression of the toxin genes. The study of txeR gene regulation in C. difficile was made possible by introduction of a mobilizable, replicative plasmid via conjugation with E. coli . |
| Databáze: | OpenAIRE |
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