TY - JOUR
T1 - A three-component dicamba O-demethylase from Pseudomonas maltophilia, strain DI-6
T2 - Purification and characterization
AU - Chakraborty, Sarbani
AU - Behrens, Mark
AU - Herman, Patricia L.
AU - Arendsen, Alexander F.
AU - Hagen, Wilfred R.
AU - Carlson, Deborah L.
AU - Wang, Xiao Zhuo
AU - Weeks, Donald P.
N1 - Funding Information:
This research was supported by funds from United AgriProducts, Inc., ConAgra, Inc., the Consortium for Plant Biotechnology Research, and the Nebraska Research Initiative. We thank Dr. John Golbeck and Dr. Stephen Ragsdale for their useful suggestions and we are grateful to Dr. Joseph Barycki for his help and advice with sizing column chromatography.
Funding Information:
This work was supported by funds from United Agri Products, Inc., ConAgra, Inc., and the Consortium for Plant Biotechnology Research, Inc. and is published as Journal Series No. 14703 of the University of Nebraska Agricultural Research Division.
PY - 2005/5/1
Y1 - 2005/5/1
N2 - Dicamba O-demethylase is a multicomponent enzyme that catalyzes the conversion of the herbicide 2-methoxy-3,6-dichlorobenzoic acid (dicamba) to 3,6-dichlorosalicylic acid (DCSA). The three components of the enzyme were purified and characterized. OxygenaseDIC is a homotrimer (α)3 with a subunit molecular mass of approximately 40 kDa. FerredoxinDIC and reductaseDIC are monomers with molecular weights of approximately 14 and 45 kDa, respectively. EPR spectroscopic analysis suggested the presence of a single [2Fe-2S](2+/1+) cluster in ferredoxinDIC and a single Rieske [2Fe-2S](2+; 1+) cluster within oxygenaseDIC. Consistent with the presence of a Rieske iron-sulfur cluster, oxygenaseDIC displayed a high reduction potential of Em,7.0 = -21 mV whereas ferredoxinDIC exhibited a reduction potential of approximately Em,7.0 = -171 mV. Optimal oxygenaseDIC activity in vitro depended on the addition of Fe2+. The identification of formaldehyde and DCSA as reaction products demonstrated that dicamba O-demethylase acts as a monooxygenase. Taken together, these data suggest that oxygenaseDIC is an important new member of the Rieske non-heme iron family of oxygenases.
AB - Dicamba O-demethylase is a multicomponent enzyme that catalyzes the conversion of the herbicide 2-methoxy-3,6-dichlorobenzoic acid (dicamba) to 3,6-dichlorosalicylic acid (DCSA). The three components of the enzyme were purified and characterized. OxygenaseDIC is a homotrimer (α)3 with a subunit molecular mass of approximately 40 kDa. FerredoxinDIC and reductaseDIC are monomers with molecular weights of approximately 14 and 45 kDa, respectively. EPR spectroscopic analysis suggested the presence of a single [2Fe-2S](2+/1+) cluster in ferredoxinDIC and a single Rieske [2Fe-2S](2+; 1+) cluster within oxygenaseDIC. Consistent with the presence of a Rieske iron-sulfur cluster, oxygenaseDIC displayed a high reduction potential of Em,7.0 = -21 mV whereas ferredoxinDIC exhibited a reduction potential of approximately Em,7.0 = -171 mV. Optimal oxygenaseDIC activity in vitro depended on the addition of Fe2+. The identification of formaldehyde and DCSA as reaction products demonstrated that dicamba O-demethylase acts as a monooxygenase. Taken together, these data suggest that oxygenaseDIC is an important new member of the Rieske non-heme iron family of oxygenases.
KW - Dicamba
KW - Ferredoxin
KW - Multicomponent enzyme
KW - O-Demethylase
KW - Oxygenase
KW - Pseudomonas maltophilia
KW - Reductase
KW - Rieske non-heme oxygenase
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U2 - 10.1016/j.abb.2005.02.024
DO - 10.1016/j.abb.2005.02.024
M3 - Article
C2 - 15820213
AN - SCOPUS:16244382394
SN - 0003-9861
VL - 437
SP - 20
EP - 28
JO - Archives of Biochemistry and Biophysics
JF - Archives of Biochemistry and Biophysics
IS - 1
ER -