title: Dynamic Response of Pseudomonas putida S12 to Sudden Addition of Toluene and the Potential Role of the Solvent Tolerance Gene trgI.
abstract: Pseudomonas putida S12 is exceptionally tolerant to various organic solvents. To obtain further insight into this bacterium's primary defence mechanisms towards these potentially harmful substances, we studied its genome wide transcriptional response to sudden addition of toluene. Global gene expression profiles were monitored for 30 minutes after toluene addition. During toluene exposure, high oxygen-affinity cytochrome c oxidase is specifically expressed to provide for an adequate proton gradient supporting solvent efflux mechanisms. Concomitantly, the glyoxylate bypass route was up-regulated, to repair an apparent toluene stress-induced redox imbalance. A knock-out mutant of trgI, a recently identified toluene-repressed gene, was investigated in order to identify TrgI function. Remarkably, upon addition of toluene the number of differentially expressed genes initially was much lower in the trgI-mutant than in the wild-type strain. This suggested that after deletion of trgI cells were better prepared for sudden organic solvent stress. Before, as well as after, addition of toluene many genes of highly diverse functions were differentially expressed in trgI-mutant cells as compared to wild-type cells. This led to the hypothesis that TrgI may not only be involved in the modulation of solvent-elicited responses but in addition may affect basal expression levels of large groups of genes.
authors.affiliation: Laboratory of Nematology, Plant Sciences, Wageningen University, Wageningen, The Netherlands; Kluyver Centre for Genomics of Industrial Fermentation, Delft, The Netherlands.
authors.forename: Rita J M
authors.initials: RJ
authors.lastname: Volkers
authors.affiliation: Laboratory of Nematology, Plant Sciences, Wageningen University, Wageningen, The Netherlands.
authors.forename: L Basten
authors.initials: LB
authors.lastname: Snoek
authors.affiliation: Corbion, Gorinchem, The Netherlands; Kluyver Centre for Genomics of Industrial Fermentation, Delft, The Netherlands.
authors.forename: Harald J
authors.initials: HJ
authors.lastname: Ruijssenaars
authors.affiliation: Department of Biotechnology,Faculty of Applied Sciences, Delft University of Technology, Delft, The Netherlands; Kluyver Centre for Genomics of Industrial Fermentation, Delft, The Netherlands.
authors.forename: Johannes H
authors.initials: JH
authors.lastname: de Winde
mesh_terms: D000222:Adaptation, Physiological / Q000235:genetics; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D003576:Electron Transport Complex IV / Q000235:genetics / Q000378:metabolism; D020869:Gene Expression Profiling; D015964:Gene Expression Regulation, Bacterial; D055786:Gene Knockout Techniques; D016680:Genome, Bacterial; D006038:Glyoxylates / Q000378:metabolism; D058977:Molecular Sequence Annotation; D010084:Oxidation-Reduction; D016958:Pseudomonas putida / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D012997:Solvents / Q000494:pharmacology*; D013997:Time Factors; D014050:Toluene / Q000494:pharmacology*; D014158:Transcription, Genetic
chemical_list: D001426:Bacterial Proteins; D006038:Glyoxylates; D012997:Solvents; D014050:Toluene; D003576:Electron Transport Complex IV; C031150:glyoxylic acid