Overcoming Bottlenecks for Metabolic Engineering of Sesquiterpene Production in Tomato Fruits.

Terpenoids are a large and diverse class of plant metabolites that also includes volatile mono- and sesquiterpenes which are involved in biotic interactions of plants. Due to the limited natural availability of these terpenes and the tight regulation of their biosynthesis, there is strong interest to introduce or enhance their production in crop plants by metabolic engineering for agricultural, pharmaceutical and industrial applications. While engineering of monoterpenes has been quite successful, expression of sesquiterpene synthases in engineered plants frequently resulted in production of only minor amounts of sesquiterpenes.

The evolutionary origins of the cat attractant nepetalactone in catnip.

Catnip or catmint ( spp.) is a flowering plant in the mint family (Lamiaceae) famed for its ability to attract cats. This phenomenon is caused by the compound nepetalactone, a volatile iridoid that also repels insects.

Contribution of isopentenyl phosphate to plant terpenoid metabolism.

Plant genomes encode isopentenyl phosphate kinases (IPKs) that reactivate isopentenyl phosphate (IP) via ATP-dependent phosphorylation, forming the primary metabolite isopentenyl diphosphate (IPP) used generally for isoprenoid/terpenoid biosynthesis. Therefore, the existence of IPKs in plants raises unanswered questions concerning the origin and regulatory roles of IP in plant terpenoid metabolism. Here, we provide genetic and biochemical evidence showing that IP forms during specific dephosphorylation of IPP catalysed by a subset of Nudix superfamily hydrolases.

Orthologs of the archaeal isopentenyl phosphate kinase regulate terpenoid production in plants.

Terpenoids, compounds found in all domains of life, represent the largest class of natural products with essential roles in their hosts. All terpenoids originate from the five-carbon building blocks, isopentenyl diphosphate (IPP) and its isomer dimethylallyl diphosphate (DMAPP), which can be derived from the mevalonic acid (MVA) and methylerythritol phosphate (MEP) pathways. The absence of two components of the MVA pathway from archaeal genomes led to the discovery of an alternative MVA pathway with isopentenyl phosphate kinase (IPK) catalyzing the final step, the formation of IPP.