Expression of Clarkia S‐linalool synthase in transgenic petunia plants results in the accumulation of S‐linalyl‐β‐d‐glucopyranoside

Abstract

SummaryPetunia hybrida W115 was transformed with a Clarkia breweri S-linalool synthase cDNA (lis). Lis was expressed in all tissues analysed, and linalool was detected in leaves, sepals, corolla, stem and ovary, but not in nectaries, roots, pollen and style. However, the S-linalool produced by the plant in the various tissues is not present as free linalool, but was ef®ciently converted to non-volatile S-linalyl-b-Dglucopyranoside by the action of endogenous glucosyltransferase. The results presented demonstrate that monoterpene production can be altered by genetic modi®cation, and that the compounds produced can be converted by endogenous enzymatic activity.

Biosynthesis of plant‐derived flavor compounds

“…Metabolic engineering of the terpenoid pathway is a constantly improving tool, used for the fundamental study of terpenoid biosynthesis (Lü cker et al, 2001(Lü cker et al, , 2004Ohara et al, 2003). In addition, this tool is being used more and more for the understanding of chemical diversity in crops (Kö llner et al, 2004;Portnoy et al, 2008), as well as improvement of traits in crops such as disease and pest resistance (Kappers et al, 2005;Schnee et al, 2006;Wu et al, 2006), enhanced and altered aroma formation (Lavy et al, 2002;Lewinsohn et al, 2001;Mahmoud and Croteau, 2001) and production of medicinal compounds (Wu et al, 2006).…”

ODORANT1Regulates Fragrance Biosynthesis in Petunia Flowers

“…Transgenic petunias were obtained via Agrobacterium tumefaciens (strain GV3101 carrying plasmid pMP90)-mediated transformation, by dipping leaf cuttings in bacterial cultures (overnight at 288C, 103 dilution). Transgenic calli were selected on MS medium containing 150 mg/mL kanamycin, from which plants were subsequently regenerated (Lucker et al, 2001). Rooting plants were tested for the presence of the neomycin phosphotransferase II gene and of the RNAi construct using PCR.…”

Scent engineering: toward the goal of controlling how flowers smell

“…In contrast to LIS-transformed petunia and carnation plants [19,20], no further modification products of the primary monoterpenes were detected in these transgenic tobacco plants. In subsequent experiments, the monoterpenoid profile in these transgenic tobacco plants was further modified by introducing the mint limonene-3-hydroxylase, which catalyzes the hydroxylation of (+)-limonene to form (+)-trans-isopiperitenol [23].…”

“…LIS converts geranyl diphosphate (GPP) to (3S)-linalool, a monoterpene alcohol with a sweet, pleasant fragrance that is found in the flowers of many species. Overexpression of LIS under the control of the constitutive 35S promoter in Petunia hybrida (petunia) [19] and Dianthus caryophyllus (carnation) [20], both of which do not emit this monoterpene from either their leaves or their flowers, indeed resulted in linalool production in both leaves and flowers. However, the synthesized linalool had no effect on the olfactory properties of the flowers or vegetative parts of the transformants.…”