Open AccessModification of Cytokinins by Cauliflower Microsomal Enzymes
Author(s) -
Chong-Maw Chen,
Scott Leisner
Publication year - 1984
Publication title -
plant physiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.554
H-Index - 312
eISSN - 1532-2548
pISSN - 0032-0889
DOI - 10.1104/pp.75.2.442
Subject(s) - cytokinin , microsome , enzyme , purine , biochemistry , cytochrome , chemistry , brassica oleracea , dehydrogenase , stereochemistry , nucleoside , biology , auxin , botany , gene
N(6)-(Delta(2)-isopentenyl)Adenine and N(6)-(Delta(2)-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-beta-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.