title: Detoxification of polycyclic aromatic hydrocarbons (PAHs) in Arabidopsis thaliana involves a putative flavonol synthase.
abstract: Polycyclic aromatic hydrocarbons (PAHs) are environmental contaminants with cytotoxic, teratogenic and carcinogenic properties. Bioremediation studies with bacteria have led to the identification of dioxygenases (DOXs) in the first step to degrade these recalcitrant compounds. In this study, we characterized the role of the Arabidopsis thaliana AT5G05600, a putative DOX of the flavonol synthase family, in the transformation of PAHs. Phenotypic analysis of loss-of-function mutant lines showed that these plant lines were less sensitive to the toxic effects of phenanthrene, suggesting possible roles of this gene in PAH degradation in vivo. Interestingly, these mutant lines showed less accumulation of H2O2after PAH exposure. Transgenic lines over-expressing At5g05600 showed a hypersensitive response and more oxidative stress after phenanthrene treatments. Moreover, fluorescence spectra results of biochemical assays with the recombinant His-tagged protein AT5G05600 detected chemical modifications of phenanthrene. Taken together, these results support the hypothesis that AT5G05600 is involved in the catabolism of PAHs and the accumulation of toxic intermediates during PAH biotransformation in plants. This research represents the first step in the design of transgenic plants with the potential to degrade PAHs, leading to the development of vigorous plant varieties that can reduce the levels of these pollutants in the environment.
authors.affiliation: Department of Biology, University of Massachusetts Boston, 100 Morrissey Blvd., Boston, MA 02125, USA.
authors.forename: Juan C
authors.initials: JC
authors.lastname: Hernández-Vega
authors.affiliation: Department of Biology, University of Massachusetts Boston, 100 Morrissey Blvd., Boston, MA 02125, USA.
authors.forename: Brian
authors.initials: B
authors.lastname: Cady
authors.affiliation: Department of Biology, University of Massachusetts Boston, 100 Morrissey Blvd., Boston, MA 02125, USA.
authors.forename: Gilbert
authors.initials: G
authors.lastname: Kayanja
authors.affiliation: Department of Biology, University of Massachusetts Boston, 100 Morrissey Blvd., Boston, MA 02125, USA.
authors.forename: Anthony
authors.initials: A
authors.lastname: Mauriello
authors.affiliation: Department of Biology, University of Massachusetts Boston, 100 Morrissey Blvd., Boston, MA 02125, USA.
authors.forename: Natalie
authors.initials: N
authors.lastname: Cervantes
authors.affiliation: Department of Biology, University of Massachusetts Boston, 100 Morrissey Blvd., Boston, MA 02125, USA.
authors.forename: Andrea
authors.initials: A
authors.lastname: Gillespie
authors.affiliation: Department of Biology, University of Massachusetts Boston, 100 Morrissey Blvd., Boston, MA 02125, USA.
authors.forename: Lisa
authors.initials: L
authors.lastname: Lavia
authors.affiliation: Department of Biology, University of Massachusetts Boston, 100 Morrissey Blvd., Boston, MA 02125, USA.
authors.forename: Joshua
authors.initials: J
authors.lastname: Trujillo
authors.affiliation: Calvinstr. 25, D-24114 Kiel, Germany.
authors.forename: Merianne
authors.initials: M
authors.lastname: Alkio
authors.affiliation: Department of Biology, University of Massachusetts Boston, 100 Morrissey Blvd., Boston, MA 02125, USA. Electronic address: adan.colon-carmona@umb.edu.
authors.forename: Adán
authors.initials: A
authors.lastname: Colón-Carmona
mesh_terms: D017360:Arabidopsis / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics; D001673:Biodegradation, Environmental; D006861:Hydrogen Peroxide; D009154:Mutation; D010088:Oxidoreductases / Q000235:genetics*; D010616:Phenanthrenes / Q000032:analysis / Q000633:toxicity; D010940:Plant Proteins / Q000235:genetics*; D030821:Plants, Genetically Modified; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis* / Q000633:toxicity; D012989:Soil Pollutants / Q000032:analysis* / Q000633:toxicity
chemical_list: D010616:Phenanthrenes; D010940:Plant Proteins; D011084:Polycyclic Aromatic Hydrocarbons; D012989:Soil Pollutants; C031181:phenanthrene; D006861:Hydrogen Peroxide; D010088:Oxidoreductases; C085313:flavonol synthase
keywords: Arabidopsis thaliana; Dioxygenases; Oxidative stress; Phytoremediation; Polycyclic aromatic hydrocarbons (PAHs)