DMAPP

DMAPP, or dimethylallyl pyrophosphate (also called dimethylallyl diphosphate), is an allylic prenyl pyrophosphate that serves as a five-carbon building block in isoprenoid biosynthesis. The molecule carries a dimethylallyl group attached to a pyrophosphate moiety, enabling transfer of the isoprenoid unit in prenyltransferase-catalyzed reactions.

In the isoprenoid pathway, DMAPP condenses with isopentenyl pyrophosphate (IPP) to form geranyl pyrophosphate (GPP) via geranyl pyrophosphate synthase. Further condensations with IPP yield farnesyl pyrophosphate (FPP) and then geranylgeranyl pyrophosphate (GGPP). These prenyl pyrophosphates are precursors to a wide range of terpenoids, including monoterpenes, sesquiterpenes, diterpenes, sterols, and carotenoids.

DMAPP is produced from IPP by isomerization, catalyzed by isopentenyl-diphosphate delta isomerase (IDI). It is generated in cells through the mevalonate pathway (cytosolic in many eukaryotes and some bacteria) or the methylerythritol phosphate (MEP) pathway (in plastids and many bacteria). The balance between IPP and DMAPP helps regulate flux through the pathway and the diversity of downstream terpenoids.

As a fundamental metabolic intermediate, DMAPP is essential for the biosynthesis of a broad array of natural products and plays a central role in metabolic engineering efforts aimed at enhancing terpenoid production in microorganisms and plants.