Lipoxygenase, hydroperoxide isomerase, and hydroperoxide cyclase in young cotton seedlings.
Plant Physiol
; 67(1): 92-7, 1981 Jan.
Article
en En
| MEDLINE
| ID: mdl-16661642
Lipoxygenase was demonstrated in young cotton seedlings. It catalyzed the oxygenation of linoleic or linolenic acid, predominantly at carbon 13, and its molecular weight was estimated by gel filtration to be 100,000. Hydroperoxide isomerase was also present and converted hydroperoxylinoleic or hydroperoxylinolenic acid to alpha- or gamma-ketols. The enzyme utilized the 13-hydroperoxy isomer in preference to the 9 isomer and its molecular weight was estimated at 250,000 by gel filtration. In addition, hydroperoxide cyclase, which catalyzes the conversion of 13-hydroperoxylinolenic acid to 12-oxo-phytodienoic acid, was present. Hydroperoxide isomerase and hydroperoxide cyclase activities could not be separated by gel filtration and ion-exchange chromatography experiments, indicating the two enzyme activities may be associated with the same protein. The activities of all three enzymes were very low in the seed but increased immediately after germination, reached a maximum after 3 to 4 days, and then declined. The results suggest a role, as yet unknown, for these enzymes during early plant development.
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1
Colección:
01-internacional
Base de datos:
MEDLINE
Idioma:
En
Revista:
Plant Physiol
Año:
1981
Tipo del documento:
Article
Pais de publicación:
Estados Unidos