Production of quinolizidine alkaloids by photo mixotrophic cell suspension cultures biochemical and biogenetic aspects
Wink, M.; Hartmann, T.
Planta Medica 40(2): 149-155
ISSN/ISBN: 0032-0943 Accession: 006192998
The biosynthetic pathway of quinolizidine alkaloids is localized in leaf chloroplasts of Lupinus polyphyllus. Consequently, alkaloid production is up to 4-10 times higher in photomixotrophic cell suspension cultures of L. polyphyllus with developed chloroplasts, than in chlorophyll-free heterotrophic cultures. Cell suspension cultures of L. polyphyllus, Baptisia australis and Sarothamnus scoparius, accumulate .apprx. 2-3 orders less alkaloids as compared with the differentiated plants. In these cultures, lupanine figures as the only main alkaloid, independent of the alkaloid composition of the respective plants, which is significantly different in S. scoparius and B. australis. The lupanine pathway is basic for the quinolizidine alkaloids and that the other alkaloids such as sparteine, 13-hydroxylupanine and the respective ester alkaloids, the tricyclic angustifolines and the .alpha.-pyridone alkaloids, derive from lupanine. In cell suspension cultures, only the basic pathway is expressed, whereas the more advanced sequences are missing.