Plant anthranoid biosynthesis

含蒽酮的植物在医药上用作泻药。类蒽酮支架的生物合成被认为是由octaketide合成酶（一种III型聚酮合成酶）催化的。三种可用的重组酶形成线性八肽中间体，但不能催化其正确环化成类蒽酮产物。因此，一个辅助环化酶可能参与，最近在大麻素生物合成检测。我们将使用激发剂处理的双囊决明子细胞培养物进行生化研究，其无细胞提取物能够形成类蒽酮。分子研究将使用贯叶连翘（Hypericum perforatum）的基因组和转录组序列进行，贯叶连翘含有石楠王座金丝桃素。

Anthranoid-containing plants are medicinally used as laxatives. Biosynthesis of the anthranoid scaffold is believed to be catalyzed by octaketide synthase, a type III polyketide synthase. Three available recombinant enzymes form a linear octaketide intermediate but fail to catalyze its correct cyclization into an anthranoid product. Thus, an accessory cyclase may be involved, as recently detected in cannabinoid biosynthesis. We will carry out biochemical studies using elicitor-treated Cassia bicapsularis cell cultures, whose cell-free extracts are capable of forming anthranoids. Molecular studies will be performed using genome and transcriptome sequences of Hypericum perforatum, which contains the naphthodianthrone hypericin.