Research Advances of Key Enzymes in the Biosynthesis Pathways of Isoprenoids

Isoprenoids are a large and diverse group of natural products which play important roles in plant metabolic activities.They are also widely used in medicine and industry field,which are synthesized via two distinct pathways,the mevalonate pathway and the 1-deoxy-D-xylulose-5-phosphate pathway. 3-hydroxy-3-methylglutaryl CoA reductase(HMGR),1-deoxy-D-xylulose-5-phosphate synthase(DXS),1-deoxy-D-lxylulose-5-phosphate reductoiso-merase(DXR),isopentenyl transferases and terpene synthases are the key enzymes that regulate isoprenoids synthesis in the two pathways.The research advances of molecular cloning,genetic expression,classification,metabolism and metabolic engineering of these key enzymes were reviewed.