高粱(Sorghum bicolor L. Moench)中的氰糖苷dhurrin的含量取决于植物的年龄和生长条件。在发芽后不久,氰化物潜力最高。在这个阶段,氮肥的施用对dhurrin含量没有影响,而在较老的植物中,氮肥的施用会引起增加。在所有阶段,dhurrin的含量与两种生物合成酶CYP79A1和CYP71E1的活性以及这两种酶的蛋白质和mRNA水平密切相关。在发育过程中,CYP79A1的活性低于CYP71E1的活性,这表明CYP79A1催化dhurrin合成的速率限制步骤,这与使用暗化的幼苗已经显示的结果一致。dhurrin合成的位置在植物发育过程中从叶子转移到茎。综合结果表明,高粱中的dhurrin含量主要由生物合成酶CYP79A1和CYP71E1的转录调控决定。
The content of the cyanogenic glucoside dhurrin in sorghum (Sorghum bicolor L. Moench) varies depending on plant age and growth conditions. The cyanide potential is highest shortly after onset of germination. At this stage, nitrogen application has no effect on dhurrin content, whereas in older plants, nitrogen application induces an increase. At all stages, the content of dhurrin correlates well with the activity of the two biosynthetic enzymes, CYP79A1 and CYP71E1, and with the protein and mRNA level for the two enzymes. During development, the activity of CYP79A1 is lower than the activity of CYP71E1, suggesting that CYP79A1 catalyzes the rate-limiting step in dhurrin synthesis as has previously been shown using etiolated seedlings. The site of dhurrin synthesis shifts from leaves to stem during plant development. In combination, the results demonstrate that dhurrin content in sorghum is largely determined by transcriptional regulation of the biosynthetic enzymes CYP79A1 and CYP71E1.
高粱(Sorghum bicolor L. Moench)中的氰糖苷dhurrin的含量取决于植物的年龄和生长条件。在发芽后不久,氰化物潜力最高。在这个阶段,氮肥的施用对dhurrin含量没有影响,而在较老的植物中,氮肥的施用会引起增加。在所有阶段,dhurrin的含量与两种生物合成酶CYP79A1和CYP71E1的活性以及这两种酶的蛋白质和mRNA水平密切相关。在发育过程中,CYP79A1的活性低于CYP71E1的活性,这表明CYP79A1催化dhurrin合成的速率限制步骤,这与使用暗化的幼苗已经显示的结果一致。dhurrin合成的位置在植物发育过程中从叶子转移到茎。综合结果表明,高粱中的dhurrin含量主要由生物合成酶CYP79A1和CYP71E1的转录调控决定。
Focused and nontargeted approaches were used to assess the impact associated with introduction of new high-flux pathways in