青蒿倍半萜合酶(环化酶)研究进展

Advances in Sesquiterpene Synthases Cyclases of Artemisia annua

摘要:

青蒿素是从中药青蒿中分离得到的抗疟有效单体，是含有过氧基团的新型倍半萜内酯化合物，是目前世界上最有效的疟疾治疗药物。青蒿素的生物合成途径属于类异戊二烯代谢途径中的倍半萜类分支途径，倍半萜合酶是该途径的关键酶之一，目前已从青蒿中克隆了多个倍半萜合酶基因。综述了青蒿中已克隆的几种倍半萜合酶基因的研究进展。

Abstract:

Artemisinin，a new and a very potent antimalarial drug，is produced by the plant Artemisia annua L. with a very low yield ranging from 0.01％ to 0.8% on a dry-weight basis. This makes artemisinin an expensive drug. Several studies reported chemical synthesis of the artemisinin，but none of them seems a viable economical alternative compared with the isolation of artemisinin from the plant. Hence， a higher artemisinin concentration in the plant is necessary for cheap antimalarial drug production. Many types of cyclic sesquiterpenes in Artemisia annua have been characterized to date，each derived from the common cyclic precursor FDP in a reaction catalyzed by a sesquiterpene synthase. Sesquiterpene synthases are widely regarded as the rate-determining regulatory enzymes in the pathways they participate，and a number of sesquiterpene synthases have been cloned from Artemisia annua up to now. This report is a brief review on the following sesquiterpene synthases: epi-cedrol synthase，amorpha-4，11-diene synthase，β-caryophyllene synthase，(E)-β-farnesene synthase，germacrene A synthase，as well as a new sesquiterpene synthase whose function remains largely unknown. The report is of help for a better understanding of metabolic engineering of Artemisia annua.