Plants produce many types of terpenoids that are all generated from the same precursors: IPP and its isomer DMAPP
, which are catalyzed by their corresponding enzymes to synthesize geranyl diphosphate (GPP), farnesyl diphosphate (FPP) and geranylgeranyldiphosphate (GGPP; Tholl, 2006).
Since the discovery of the MVA pathway, it had been widely accepted that IPP and DMAPP were formed only through this pathway in all living organisms.
In 1996, Rohmer identified the first reaction step of an alternative MVA-independent pathway for the formation of IPP and DMAPP in E.
coli, DXP is a biosynthetic intermediate not only for IPP and DMAPP but also for thiamine and pyridoxal (Fig.
As mentioned above, DXP is a precursor not only for IPP and DMAPP but also for thiamine and pyridoxal.
coli HMBDP reductase reduces HMBDP in the presence of ferredoxin and NADPH to yield a 5:1 mixture of IPP and DMAPP.
2) catalyzes an essential reaction in the MVA pathway by converting IPP to DMAPP.
coli, catalyzes the isomerization of IPP to produce DMAPP in the presence of both flavin mononucleotide (FMN) and NAD(P)H.