ME: Cloning of Elisabethatriene Cyclase for Use in the Synthesis of Diterpenes

Florida Atlantic University, Boca Raton FL

Investigators

Abstract

Marine organisms have proven to be a prolific source of novel, biologically active natural products. A growing number of these are entering clinical trials and many more are in preclinical development. In general, the production of these compounds through synthesis is not feasible on a commercial scale and consequently, the supply of such compounds presents an escalating problem. This project is directed at the development of seco-pseudopterosins and related metabolites, anti-inflammatory agents from the soft coral Pseudopterogorgia elisabethae. These compounds have been shown to be anti-inflammatory and analgesic agents in mouse ear models with potencies superior to that of pseudopterosins which are in clinical use, and existing drugs such as indomethacin. A biotechnological production method of these compounds will be developed based on the cloning of a key biosynthetic enzyme. In addition to addressing the supply issue of these specific metabolites, completion of these goals will provide useful models for the development of a growing number of anti-inflammatory terpenes being discovered from marine invertebrates. Since all of the pseudopterosin used commercially is obtained through collections from nature, success with this project will provide a sustainable source of these valuable compounds and save delicate reef environments from the effects of large scale collecting. The synthesis of the targeted anti-inflammatory agents will be approached as follows. Firstly, the first biosynthetic intermediate will be generated by sequencing the coral's diterpene cyclase and cloning this into E. coli. via the construction of a P. elisabethae cDNA library. The cyclase product will serve as a key intermediate in the syntheses and will be modified to the seco-pseudopterosin aglycone by chemical methods. This would then set the state for the ultimate glycosylation to complete the synthesis of the seco-pseudopterosins. ( This last step is not a goal of the present project.) This research represents a collaboration between two labs with complementary expertise. R. Kerr (PI, FAU) will conduct the natural products chemistry, enzymology and some of the molecular work J. Lopez (Co-PI, HBOI) will compete the cDNA library construction and work with Kerr on the cloning experiments.