title: Assimilatory detoxification of herbicides by Delftia acidovorans MC1: induction of two chlorocatechol 1,2-dioxygenases as a response to chemostress.
abstract: Proteome analysis of bacteria that can detoxify harmful organic compounds enables the discovery of enzymes involved in the biodegradation of these substances and proteins that protect the cell against poisoning. Exposure of Delftia acidovorans MC1 to 2,4-dichlorophenoxypropionic acid and its metabolites 2,4-dichlorophenol and 3,5-dichlorocatechol during growth on pyruvate as a source of carbon and energy induced several proteins. Contrary to the general hypothesis that lipophilic or reactive compounds induce heat shock or oxidative stress proteins, no induction of the GroEL, DnaK and AhpC proteins that were used as markers for the induction of heat shock and oxidative stress responses was observed. However, two chlorocatechol1,2-dioxygenases, identified by amino terminal sequence analysis, were induced. Both enzymes catalyse the conversion of 3,5-dichlorocatechol to 2,4-dichloro-cis,cis-muconate indicating that biodegradation is a major mechanism of resistance in the detoxifying bacterium D. acidovorans MC1.
authors.affiliation: UFZ - Centre for Environmental Research Leipzig-Halle, Department of Environmental Microbiology, PF 500135, 04301 Leipzig, Germany1.
authors.forename: Dirk
authors.initials: D
authors.lastname: Benndorf
authors.affiliation: UFZ - Centre for Environmental Research Leipzig-Halle, Department of Environmental Microbiology, PF 500135, 04301 Leipzig, Germany1.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Babel
mesh_terms: D020562:Betaproteobacteria / Q000187:drug effects / Q000201:enzymology* / Q000378:metabolism; D001673:Biodegradation, Environmental; D002396:Catechols / Q000378:metabolism* / Q000494:pharmacology*; D018834:Chaperonin 60 / Q000378:metabolism; D049308:Dioxygenases; D015180:Electrophoresis, Gel, Two-Dimensional / Q000379:methods; D004790:Enzyme Induction; D029968:Escherichia coli Proteins; D018840:HSP70 Heat-Shock Proteins / Q000378:metabolism; D006360:Heat-Shock Proteins / Q000737:chemistry / Q000378:metabolism*; D018869:Heat-Shock Response; D006540:Herbicides / Q000378:metabolism*; D008969:Molecular Sequence Data; D010105:Oxygenases / Q000096:biosynthesis* / Q000378:metabolism; D011422:Propionates / Q000378:metabolism*; D012808:Sigma Factor / Q000235:genetics / Q000378:metabolism*
chemical_list: C473754:2,4-dichlorophenoxypropionic acid; D002396:Catechols; D018834:Chaperonin 60; D029968:Escherichia coli Proteins; D018840:HSP70 Heat-Shock Proteins; D006360:Heat-Shock Proteins; D006540:Herbicides; D011422:Propionates; D012808:Sigma Factor; D010105:Oxygenases; D049308:Dioxygenases; C044173:chlorocatechol 1,2-dioxygenase; C063842:dnaK protein, E coli