Induction of a novel cytochrome P450 (CYP96 family) in periwinkle (Catharanthus roseus) cells induced for terpenoid indole alkaloid production

A full-length cDNA (designated CDS1) that encodes a cytochrome P450 enzyme (P450) was isolated by combining differential screening and asymmetric PCR amplifications of cDNA libraries from periwinkle (Catharanthus roseus) cell cultures induced for terpenoid indole alkaloid (TIA) synthesis. The deduced polypeptide has 501 aminoacids, a heme-binding cystein domain (the P450 signature), residues conserved in most P450s, and a hydrophobic N-terminal region acting as membrane anchor. CDS1 was assigned as the first member of a new subfamily: CYP96C1. Hybridization of genomic periwinkle DNA with CYP96C1 probe suggested that the protein is encoded by a single-copy gene. CYP96C1 transcripts accumulated only in alkaloid-producing cells showing an association between the induction of the biosynthesis of TIAs and the expression of CYP96C1. The putative function of the CYP96C1 protein is discussed. (C) 1999 Elsevier Science Ireland Ltd. All rights reserved.