Isochorismate is an intermediate in 2,3-dihydroxybenzoic acid biosynthesis in Catharanthus roseus cell cultures

To study the intermediacy of isochorismate in the biosynthesis of 2,3-dihydroxybenzoic acid (2,3-DHBA) in Catharanthus roseus cell cultures, an incorporation study using 〚1-13C〛glucose was carried out. Based on a significantly different enrichment at the positions of C-2 and C-6 in 2,3-DHBA, and low incorporation at C-7, it is concluded that indeed isochorismate is an intermediate. In the case of phenylalanine as an intermediate, a symmetrical partitioning of the label between C-2 and C-6 would occur, and C-7 would be strongly labeled.