Reaction: dehydrosecodine = tabersonine
For diagram of reaction, click here and mechanism click here
Other name(s): TS (gene name)
Systematic name: dehydrosecodine cyclase (tabersonine-forming)
Comments: The enzyme, characterized from the plant Catharanthus roseus (Madagascar periwinkle), is a carboxylesterase-like cyclase that catalyses a regio- and enantiodivergent [4+2] cycloaddition reaction to generate the aspidosperma scaffold of tabersonine. cf. EC 5.5.1.37, catharanthine synthase.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number:
References:
1. Caputi, L., Franke, J., Farrow, S.C., Chung, K., Payne, R.ME., Nguyen, T.D., Dang, T.T., Soares Teto Carqueijeiro, I., Koudounas, K., Duge de Bernonville, T., Ameyaw, B., Jones, D.M., Vieira, I.JC., Courdavault, V. and O'Connor, S.E. Missing enzymes in the biosynthesis of the anticancer drug vinblastine in Madagascar periwinkle. Science 360 (2018) 1235-1239. [PMID: 29724909]
2. DeMars, M.D., 2nd and O'Connor, S.E. Evolution and diversification of carboxylesterase-like [4+2] cyclases in aspidosperma and iboga alkaloid biosynthesis. Proc. Natl. Acad. Sci. USA 121 (2024) e2318586121. [PMID: 38319969]