A pathogen-inducible divinyl ether synthase (CYP74D) from elicitor-treatedpotato suspension cells

In elicitor-treated potato cells, 9-lipoxygenase-derived oxylipins accumula te with the divinyl ether colneleic acid as the major metabolite. Here, the identification of a potato cDNA is described, whose predicted amino acid s equence corresponds to divinyl ether synthases, belonging to the recently i dentified new P450 subfamily CYP74D. The recombinant protein was expressed in Escherichia coli and shown to metabolize 9-hydroperoxy linoleic acid to colneleic acid at pH 6.5. This fatty acid derivative has been implicated in functioning as a plant antimicrobial compound. RNA blot analyses revealed accumulation of divinyl ether synthase transcripts both upon infiltration o f potato leaves with Pseudomonas syringae and after infection with Phytopht hora infestans. (C) 2001 Federation of European Biochemical Societies. Publ ished by Elsevier Science B.V. All rights reserved.