TY - JOUR
T1 - Enzymatic basis for fungicide removal by Elodea canadensis
AU - Dosnon-Olette, Rachel
AU - Schröder, Peter
AU - Bartha, Bernadett
AU - Aziz, Aziz
AU - Couderchet, Michel
AU - Eullaffroy, Philippe
N1 - Funding Information:
Acknowledgments This work is a part of the “Contrat d’objectifs AQUAL” and is funded by the city of Reims and the Agence de l’Eau Seine-Normandie. A part of this work was funded by the COST 859 (European Cooperation in Science and Technology; STSM-859-03760). The authors are grateful to Rudolf Harpaintner and Christian Huber (Helmholtz-Zentrum München, Germany) for their help with the HPLC analysis of glycosylated substrates and to Valérie Page (EPFL, Switzerland) for P450 protocol.
PY - 2011/7
Y1 - 2011/7
N2 - Purpose: Plants can absorb a diversity of natural and man-made toxic compounds for which they have developed diverse detoxification mechanisms. Plants are able to metabolize and detoxify a wide array of xenobiotics by oxidation, sugar conjugation, glutathione conjugation, and more complex reactions. In this study, detoxification mechanisms of dimethomorph, a fungicide currently found in aquatic media were investigated in Elodea canadensis. Methods: Cytochrome P450 (P450) activity was measured by an oxygen biosensor system, glucosyltransferases (GTs) by HPLC, glutathione S-transferases (GSTs), and ascorbate peroxidase (APOX) were assayed spectrophotometrically. Results: Incubation of Elodea with dimethomorph induced an increase of the P450 activity. GST activity was not stimulated by dimethomorph suggesting that GST does not participate in dimethomorph detoxification. In plants exposed to dimethomorph, comparable responses were observed for GST and APOX activities showing that the GST was more likely to play a role in response to oxidative stress. Preincubation with dimethomorph induced a high activity of O- and N-GT, it is therefore likely that both enzymes participate in the phase II (conjugation) of dimethomorph detoxification process. Conclusions: For the first time in aquatic plants, P450 activity was shown to be induced by a fungicide suggesting a role in the metabolization of dimethomorph. Moreover, our finding is the first evidence of dimethomorph and isoproturon activation of cytochrome P450 multienzyme family in an aquatic plant, i.e., Elodea (isoproturon was taken here as a reference molecule). The detoxification of dimetomorph seems to proceed via hydroxylation, and subsequent glucosylation, and might yield soluble as well as cell wall bound residues.
AB - Purpose: Plants can absorb a diversity of natural and man-made toxic compounds for which they have developed diverse detoxification mechanisms. Plants are able to metabolize and detoxify a wide array of xenobiotics by oxidation, sugar conjugation, glutathione conjugation, and more complex reactions. In this study, detoxification mechanisms of dimethomorph, a fungicide currently found in aquatic media were investigated in Elodea canadensis. Methods: Cytochrome P450 (P450) activity was measured by an oxygen biosensor system, glucosyltransferases (GTs) by HPLC, glutathione S-transferases (GSTs), and ascorbate peroxidase (APOX) were assayed spectrophotometrically. Results: Incubation of Elodea with dimethomorph induced an increase of the P450 activity. GST activity was not stimulated by dimethomorph suggesting that GST does not participate in dimethomorph detoxification. In plants exposed to dimethomorph, comparable responses were observed for GST and APOX activities showing that the GST was more likely to play a role in response to oxidative stress. Preincubation with dimethomorph induced a high activity of O- and N-GT, it is therefore likely that both enzymes participate in the phase II (conjugation) of dimethomorph detoxification process. Conclusions: For the first time in aquatic plants, P450 activity was shown to be induced by a fungicide suggesting a role in the metabolization of dimethomorph. Moreover, our finding is the first evidence of dimethomorph and isoproturon activation of cytochrome P450 multienzyme family in an aquatic plant, i.e., Elodea (isoproturon was taken here as a reference molecule). The detoxification of dimetomorph seems to proceed via hydroxylation, and subsequent glucosylation, and might yield soluble as well as cell wall bound residues.
KW - Cytochrome P450
KW - Detoxification
KW - Glucosyltransferase
KW - Glutathione S-transferase
KW - Pesticide
KW - Phytoremediation
UR - http://www.scopus.com/inward/record.url?scp=79960098741&partnerID=8YFLogxK
U2 - 10.1007/s11356-011-0460-1
DO - 10.1007/s11356-011-0460-1
M3 - Article
C2 - 21301975
AN - SCOPUS:79960098741
SN - 0944-1344
VL - 18
SP - 1015
EP - 1021
JO - Environmental Science and Pollution Research
JF - Environmental Science and Pollution Research
IS - 6
ER -