Elucidation of strigol biosynthesis in Menispermum dauricum

合成了氘标记的5-脱氧独脚金醇，建立了独脚金内酯的超高效液相色谱-电喷雾质谱分析方法。当蝙蝠葛的根培养物，这是一个高生产商独脚金醇，与氘标记的5-脱氧独脚金醇喂养，转换的5-脱氧独脚金醇到独脚金醇没有检测到。这表明蝙蝠葛中独脚金醇不是通过5-脱氧独脚金醇生物合成的。另一方面，GR 24，一种合成的独脚金内酯类似物，被根培养物代谢为7-OH-GR 24。接下来，将氘标记的5-脱氧独脚金醇施用于高产高粱酚的高粱栽培品种，两色高粱（Sorcium bicolor（L.）Moench，并转化为高粱醇进行了研究。5-脱氧独脚金醇被代谢为高粱醇，并且转化被P450抑制剂抑制。这些结果表明，高粱醇是由5-脱氧独脚金醇通过P450依赖性的C-9羟基化生物合成的。

Deuterium-labeled 5-deoxystrigol was synthesized, and the analytical method for strigolactones by UPLC-ESI-MS was established. When the root-cultures of Menispermum dauricum, which are a high producer of strigol, were fed with deuterium-labeled 5-deoxystrigol, the conversion of 5-deoxystrigol to strigol was not detected. This suggests that strigol is not biosynthesized via 5-deoxystrigol in Menispermum dauricum. On the other hand, GR24, a synthetic strigolactone analog, was metabolized to 7-OH-GR24 by the root cultures. Next, deuterium-labeled 5-deoxystrigol was administered to hydroponics of a high sorgomol-producing sorghum cultivar, Sorghum bicolor (L.) Moench, and conversion to sorgomol was investigated. 5-deoxystrigol was metabolized to sorgomol and the conversion was inhibited by a P450 inhibitor. These results suggest that sorgomol is biosynthesized from 5-deoxystrigol via a P450-dependent C-9 hydroxylation.