Component of the floral volatile benzenoid/phenylpropanoid (FVBPs) biosynthetic pathway (PubMed:19811620). Mediates the conversion of chorismate to prephenate, thus coupling metabolites from the shikimate pathway to the synthesis of FVBPs in the corolla (PubMed:19811620). chorismate = prephenate Allosterically activated by tryptophan but not by tyrosine and phenylalanine. Metabolic intermediate biosynthesis; prephenate biosynthesis; prephenate from chorismate: step 1/1. Homodimer. Mostly expressed in petal tubes and petal limbs, and, to a lower extent, in stigmas, anthers, sepals, roots, stems and leaves. Accumulates during flower development with highest levels in open flowers, at anthesis, and fades out as flowers are senescing. Triggered by EOBI in flowers. Reduced emission of floral volatile benzenoid/phenylpropanoid (FVBP) compounds associated with a strongly impaired chorismate mutase activity in corolla tissues.