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. 1984 Jun;75(2):442–446. doi: 10.1104/pp.75.2.442

Modification of Cytokinins by Cauliflower Microsomal Enzymes 1

Chong-Maw Chen 1, Scott M Leisner 1
PMCID: PMC1066926  PMID: 16663640

Abstract

N6-(Δ2-isopentenyl)Adenine and N6-(Δ2-isopentenyl)adenosine were hydroxylated, respectively, to 6-(4-hydroxy-3-methyl-trans-2-butenylamino)purine and 6-(4-hydroxy-3-methyl-trans-2-butenylamino) -9-β-ribofuranosylpurine in the presence of NADPH and the microsomal fraction from cauliflowers (Brassica oleracea L.). The hydroxylating reaction was completely inhibited by 10 millimolars metyrapone and partially inactivated by 10-minute treatment of the microsomal preparation with ethylene. The cytokinins were also dealkylated by the microsomal enzymes and formed adenine from cytokinin base and adenosine from cytokinin nucleoside. These results suggest that plant cytochrome P-450 is involved in the conversion of one type of cytokinin to another, and in the modification of cytokinin molecules.

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Selected References

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