title: In vitro and in vivo evidence for the inhibition of brassinosteroid synthesis by propiconazole through interference with side chain hydroxylation.
abstract: We carried out the biochemical evaluation of the target site of propiconazole in BR biosynthesis. Applying BR biosynthesis intermediates to Arabidopsis seedlings grown in the presence of propiconazole under dark condition, we found that the target site of propiconazole in BR biosynthesis can be identified among the C22 and C23 side chain hydroxylation steps from campestanol to teasterone. Using differential spectra techniques to determine the binding affinity of propiconazole to CYP90D1, which is responsible for C23 hydroxylation of BR, we found that propiconazole induced typical type II binding spectra in response to purified recombinant CYP90D1 and the Kd value was found approximately 0.76 μM.
authors.affiliation: a Department of Biotechnology , Faculty of Bioresource Sciences, Akita Prefectural University , Shimoshinjo Nakano, Akita , Japan.
authors.forename: Keimei
authors.initials: K
authors.lastname: Oh
authors.affiliation: a Department of Biotechnology , Faculty of Bioresource Sciences, Akita Prefectural University , Shimoshinjo Nakano, Akita , Japan.|b National Agricultural Research Center, National Agriculture and Food Research Organization , Kannondai, Tsukuba , Ibaraki , Japan.
authors.forename: Tadashi
authors.initials: T
authors.lastname: Matsumoto
authors.affiliation: a Department of Biotechnology , Faculty of Bioresource Sciences, Akita Prefectural University , Shimoshinjo Nakano, Akita , Japan.
authors.forename: Tomoki
authors.initials: T
authors.lastname: Hoshi
authors.affiliation: a Department of Biotechnology , Faculty of Bioresource Sciences, Akita Prefectural University , Shimoshinjo Nakano, Akita , Japan.
authors.forename: Yuko
authors.initials: Y
authors.lastname: Yoshizawa
mesh_terms: D017360:Arabidopsis / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000378:metabolism; D060406:Brassinosteroids / Q000096:biosynthesis*; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism; D006900:Hydroxylation / Q000187:drug effects; D007700:Kinetics; D011485:Protein Binding / Q000187:drug effects; D011994:Recombinant Proteins / Q000378:metabolism; D036226:Seedlings / Q000187:drug effects / Q000378:metabolism; D014230:Triazoles / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D029681:Arabidopsis Proteins; D060406:Brassinosteroids; D011994:Recombinant Proteins; D014230:Triazoles; C045950:propiconazole; D003577:Cytochrome P-450 Enzyme System
keywords: Brassinosteroid biosynthesis inhibitor; Propiconazole; plant growth regulation; plant hormone