Developmental regulation of aldoxime formation in seedlings and mature plants of Chinese cabbage (Brassica campestris ssp. pekinensis) and oilseed rape (Brassica napus): Glucosinolate and IAA biosynthetic enzymes

Publikation: Beitrag in FachzeitschriftForschungsartikelBeigetragenBegutachtung

Beitragende

  • Richard Bennett - , Rothamsted Research (Autor:in)
  • Jutta Ludwig-Muller - , Johann Wolfgang Goethe-Universität Frankfurt am Main (Autor:in)
  • Guy Kiddle - , Rothamsted Research (Autor:in)
  • Willy Hilgenberg - , Johann Wolfgang Goethe-Universität Frankfurt am Main (Autor:in)
  • Roger Wallsgrove - , Rothamsted Research (Autor:in)

Abstract

The first steps in the biosynthesis of glucosinolates and indole-3-acetic acid (IAA) in oilseed rape (Brassica napus L.) and Chinese cabbage (Brassica campestris ssp. pekinensis) involve the formation of aldoximes. In rape the formation of aldoximes from chain-extended amino acids, for aromatic and aliphatic glucosinolate biosynthesis, is catalysed by microsomal flavin-containing monooxygenases. The formation of indole-3-aldoxime from l-tryptophan, the potential precursor of both indole-3-acetic acid and indolyl-glucosinolates, is catalysed by several microsomal peroxidases. The biosynthesis of glucosinolates and indole-3-acetic acid was shown to be under developmental control in oilseed rape and Chinese cabbage. No monooxygenase activities were detected in cotyledons or old leaves of either species. The highest monooxygenase activities were found in young expanding leaves; as the leaves reached full expansion and matured the activities decreased rapidly. The indole-aldoxime-forming activity was found in all of the tissues analysed, but there was also a clear decrease in foliar activity with maturity in leaves of rape and Chinese cabbage. Partial characterisation of the Chinese cabbage monooxygenases showed that they have essentially identical properties to the previously characterised rape enzymes; they are not cytochrome P450-type enzymes, but resemble flavin-containing monooxygenases. No monooxygenase inhibitors were detected in microsomes prepared from either cotyledons or old leaves.

Details

OriginalspracheEnglisch
Seiten (von - bis)239-244
Seitenumfang6
FachzeitschriftPlanta: an international journal of plant biology
Jahrgang196
Ausgabenummer2
PublikationsstatusVeröffentlicht - Mai 1995
Peer-Review-StatusJa
Extern publiziertJa

Schlagworte

ASJC Scopus Sachgebiete

Schlagwörter

  • Aldoxime biosynthesis, Auxin biosynthesis, Brassica, Glucosinolate