Overexpression of tropinone reductases alters alkaloid composition in Atropa belladonna root cultures
The medicinally applied tropane alkaloids hyoscyamine and scopolamine are produced in Atropa belladonna L. and in a small number of other Solanaceae. Calystegines are nortropane alkaloids that derive from a branching point in the tropane alkaloid biosynthetic pathway. In A. belladonna root cultures,...
| Veröffentlicht in: | Journal of experimental botany. - 1985. - 56(2005), 412 vom: 18. Feb., Seite 645-52 |
|---|---|
| 1. Verfasser: | |
| Weitere Verfasser: | , , , |
| Format: | Aufsatz |
| Sprache: | English |
| Veröffentlicht: |
2005
|
| Zugriff auf das übergeordnete Werk: | Journal of experimental botany |
| Schlagworte: | Journal Article Research Support, Non-U.S. Gov't Alkaloids Alcohol Oxidoreductases EC 1.1.- tropinone reductase EC 1.1.1.236 |
| Zusammenfassung: | The medicinally applied tropane alkaloids hyoscyamine and scopolamine are produced in Atropa belladonna L. and in a small number of other Solanaceae. Calystegines are nortropane alkaloids that derive from a branching point in the tropane alkaloid biosynthetic pathway. In A. belladonna root cultures, calystegine molar concentration is 2-fold higher than that of hyoscyamine and scopolamine. In this study, two tropinone reductases forming a branching point in the tropane alkaloid biosynthesis were overexpressed in A. belladonna. Root culture lines with strong overexpression of the transcripts contained more enzyme activity of the respective reductase and enhanced enzyme products, tropine or pseudotropine. High pseudotropine led to an increased accumulation of calystegines in the roots. Strong expression of the tropine-forming reductase was accompanied by 3-fold more hyoscyamine and 5-fold more scopolamine compared with control roots, and calystegine levels were decreased by 30-90% of control. In some of the transformed root cultures, an increase of total tropane alkaloids was observed. Thus, transformation with cDNA of tropinone reductases successfully altered the ratio of tropine-derived alkaloids versus pseudotropine-derived alkaloids |
|---|---|
| Beschreibung: | Date Completed 09.05.2005 Date Revised 15.11.2006 published: Print-Electronic Citation Status MEDLINE |
| ISSN: | 1460-2431 |