絲狀真菌所產生的二次代謝物為低分子量、結構複雜且具有豐富生物活性的產物，如青黴菌所產生的penicillin、土麴菌所產生的lovastatin等，在醫療上具有相當大的貢獻。目前的研究對於調控二次代謝物相關的基因有很大的發展潛力，應用價值也相當廣泛；本研究乃探討土麴菌 (Aspergillus terreus) ana基因叢集轉譯之酵素催化形成出結構複雜的二次代謝物acetylaszonalenin及其生物活性分析。 AnaPS基因經剔除後，土麴菌喪失產生acetylaszonalenin的能力；但加入原本應由anaPS催化所產生的前驅物後，依然可遵循此一生合成路徑，產生acetylaszonalenin，證明anaPS確實參與acetylaszonalenin生合成；與固態培養相比，以液態方式培養，餵養生合成路徑之前驅物benzodiazepinedione的量較少但二次代謝產物所生合成的量較多，且菌絲型態亦不受影響，顯示在本實驗中液態培養方式優於固態。 本研究成功以真菌為小型工廠，以半生合成的方式，獲得結構複雜、人工不易合成之化合物，建立半生合成的平台，並且藉由培養方式的調整獲取二次代謝物的較佳實驗條件。期望此半生合成的方法對化學合成的領域有所貢獻。 A putative acetylaszonlenin-biosynthetic gene cluster was identified in the genome sequence of Neosartorya fischeri and Aspergillus terreus. This cluster consists of three genes, anaPS, anaPT, and anaAT. In the previous study, a anaPS strain of A. terreus NIH2624 was created and examination of the secondary metabolite profiles of the anaPS strain in comparison with the wild type strain clearly showed that acetylaszonlenin is missing in the deletion strain. N. fischeri NRRL181 and A. terreus NIH2624, and A. terreus anaPS strains are from Dr. Clay Wang’s laboratory in University of Southern California. The precursors of acetylaszonalenin, benzodiazepinedione, catalyzed by anaPS in the biosynthetic pathway of acetylaszonalenin were chemically synthesized. A. terreus anaPS strain was cultured and fed with benzodiazepinedione and its analogues of benzodiazepinedione. Secondary metabolites from N. flscheri and A. terreus were identified by HPLC and LC/MS. Acetylazonalenin was successfully obtained in A. terreus anaPS strain after feeding benzodiazepinedione. In this research, we successfully demonstrated the semi-biosynthetic approaches in the preparation acetylaszonalenin and its analogues. We keep on try our effort to optimize the growth condition for the bio-plant. The fungal genomic mining and biosynthesis of secondary metabolites will investigate continuously.
