植物2,3-氧化鲨烯环化酶的研究进展

Research Progress in plant 2,3-oxidosqualene Cyclase

三萜化合物是一类具有重要生物活性的天然产物,其生物合成途径受到极大的关注,在植物中它们都是由异戊二烯代谢途径,经过2,3-氧化鲨烯环化及羟基化和糖基化修饰产生,2,3-氧化鲨烯环化酶(OSC)催化底物环化生成三萜骨架是三萜结构多样和生物活性的基础。本综述对植物OSC基因的研究方法、克隆和功能鉴定、进化及酶结构和催化机制等各个方面的研究进展进行了综述,为植物三萜代谢途径解析,特别是OSC功能的研究提供了依据。最后,从酶挖掘、结构预测和定向进化三个方面展望了植物OSC今后的发展和突破。

Triterpenoids are a class of natural active substances with important biological activities, and their biosynthetic pathway has attracted great attention in recent years. They are all produced by the plant isoprene metabolic pathway, which generates 2, 3-oxidosqualene and followed with cyclization, hydroxylation and glycosylation. Among them, 2, 3-oxidosqualene cyclase(OSC) is the key enzyme of an important branch node in triterpenoid metabolic pathway. This review summarized the research progress of plant OSC functional characterizing methods, gene cloning and function identification, OSCs evolution, enzyme structure and catalytic mechanism, which provided a basis for the analysis of plant triterpene metabolic pathway, especially for the study of OSC functions. Finally, the future development and breakthrough of plant OSCs are prospected in enzyme mining, structure prediction and directed evolution etc.