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

高等陆生植物被子植物产生多种具有生物活性的二萜类化合物，如抗生素、拒食剂和植物激素等。苔藓、地钱和蕨类植物等低等植物都能产生二萜类化合物，但其生物合成途径尚不清楚。为了阐明陆生植物二萜合成的进化，克隆了低等植物二萜合成基因，并对其酶学功能进行了研究。我们在此证明，新的二萜环化酶基因的克隆从蕨类植物，卷柏和苔藓灰藓plumaeforme。此外，我们显示了详细的催化机制，内贝壳杉烯合成使用嵌合酶在苔藓和苔。

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.