Studies for the biosynthetic pathway of diterpenes in lower land plants.

高等陆地植物被子植物产生多种生物活性的二萜类化合物，如抗生素、拒食性激素和植物激素。低地植物、苔藓、地钱和蕨类植物产生二萜类化合物，但二萜类化合物的生物合成途径尚未在这些低等植物中被揭示。为了阐明陆生植物二萜生物合成的进化过程，克隆了低等陆生植物二萜合成基因，并对其酶功能进行了研究。我们在这里证明了从蕨类植物卷柏和垂叶苔藓中克隆新的二萜环化酶基因。此外，我们还利用苔藓和地钱中的嵌合酶展示了Et-Kaurene合成的详细催化机理。

Higher land plants, angiosperm produces various bioactive diterpenoids as antibiotic, anti-feedant and plant hormones. The lower land plants, the moss, liverwort and fern produce the diterpenoids, however, the biosynthetic pathway of diterpenes have not been revealed in these lower plants. To elucidate the evolution of diterpene biosynthesis in land plants, diterpene synthetic genes in lower land plants was cloned, and the enzymatic functions were investigated. We herein demonstrate that the cloning of new diterpene cyclase genes from the fern, Selaginella moellendorffii and moss Hypnum plumaeforme. Additionally, we showed the detailed catalyzing mechanism of ent-kaurene synthese using the chimeric enzymes in the moss and liverwort.