Two novel 7-epi-zingiberene derivatives with biological activity from Solanum habrochaites are produced by a single cytochrome P450 monooxygenase

Abstract

AbstractSecretions from glandular trichomes potentially protect the plant against a variety of aggressors. In the tomato genus, wild species constitute a rich source of chemical diversity produced at the leaf surface by glandular trichomes. Previously, 7-epi-zingiberene produced in several accessions of Solanum habrochaites was found to confer resistance to whiteflies (Bemisia tabaci) and other insect pests. Here, we identify two derivatives of 7-epi-zingiberene from S. habrochaites that had not been reported as yet. We identified them as 9-hydroxy-zingiberene and 9-hydroxy-10,11-epoxyzingiberene. Using a combination of genetics and transcriptomics we identified a single cytochrome P450 oxygenase, ShCYP71D184 that carries out two successive oxidations to generate the two sesquiterpenoids. Bioactivity assays showed that only 9-hydroxy-10,11-epoxyzingiberene exhibits substantial toxicity against B. tabaci. In addition, both 9-hydroxy-zingiberene and 9-hydroxy-10,11-epoxyzingiberene display substantial growth inhibitory activities against a range of microorganisms, including Bacillus subtilis, Phytophtora infestans and Botrytis cinerea. Our work shows that trichome secretions from wild tomato species can provide protection against a wide variety of organisms. In addition, the availability of the genes encoding the enzymes for the pathway of 7-epi-zingiberene derivatives makes it possible to introduce this trait in cultivated tomato by precision breeding.