Scholl Yvonne, Schneider Bernd, Dräger Birgit
Institut für Pharmazeutische Biologie, Martin-Luther-Universität Halle-Wittenberg, Hoher Weg 8, D-06120 Halle/Saale, Germany.
Phytochemistry. 2003 Feb;62(3):325-32. doi: 10.1016/s0031-9422(02)00544-7.
Calystegines are nortropane alkaloids bearing between three and five hydroxyl groups in various positions. [15N]Tropinone was administered to root cultures of Calystegia sepium and the incorporation into calystegines was followed. Increase of label in calystegines was measured by one-dimensional 15N NMR and inverse-detected 2D NMR techniques. The results show that tropinone and pseudotropine are metabolites in the biosynthetic pathway of calystegines. The velocity of calystegine accumulation was followed kinetically by transfer of root cultures from 15N-enriched medium to 14N-medium and analysis by GC-MS. A constant calystegine formation with no interference by excretion or degradation was observed. A biosynthetic rate for individual calystegines at each time point was calculated, the maximum was 0.4 mg/day/g of biomass. This allowed the velocity of individual biosynthetic steps to be estimated.
旋花茄碱是在不同位置带有三个至五个羟基的降托品烷生物碱。将[15N]托品酮施用于裂叶牵牛的根培养物，并追踪其掺入旋花茄碱的情况。通过一维15N NMR和反向检测二维NMR技术测量旋花茄碱中标记物的增加。结果表明，托品酮和假托品是旋花茄碱生物合成途径中的代谢产物。通过将根培养物从富含15N的培养基转移到14N培养基并进行GC-MS分析，动力学追踪了旋花茄碱的积累速度。观察到旋花茄碱的形成恒定，没有排泄或降解的干扰。计算了每个时间点单个旋花茄碱的生物合成速率，最大值为0.4毫克/天/克生物量。这使得可以估计各个生物合成步骤的速度。
