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Title: In vitro oxidation of indoleacetic acid by soluble auxin-oxidases and peroxidases from maize roots. [Zea mays L]

Journal Article · · Plant Physiology; (USA)
DOI:https://doi.org/10.1104/pp.94.2.485· OSTI ID:5915073
; ;  [1]
  1. Institute of Plant Biology and Physiology of the University, Lausanne (Switzerland)

Soluble auxin-oxidases were extracted from Zea mays L. cv LG11 apical root segments and partially separated from peroxidases (EC 1.11.1.7) by size-exclusion chromatography. Auxin-oxidases were resolved into one main peak corresponding to a molecular mass of 32.5 kilodaltons and a minor peak at 54.5 kilodaltons. Peroxidases were separated into at least four peaks, with molecular masses from 32.5 to 78 kilodaltons. In vitro activity of indoleacetic acid-oxidases was dependent on the presence of MnCl{sub 2} and p-coumaric acid. Compound(s) present in the crude extract and several synthetic auxin transport inhibitors (including 2,3,5-triiodobenzoic acid and N-1-naphthylphthalamic acid) inhibited auxin-oxidase activity, but had no effect on peroxidases. The products resulting from the in vitro enzymatic oxidation of ({sup 3}H)indoleacetic acid were separated by HPLC and the major metabolite was found to cochromatograph with indol-3yl-methanol.

OSTI ID:
5915073
Journal Information:
Plant Physiology; (USA), Vol. 94:2; ISSN 0032-0889
Country of Publication:
United States
Language:
English