2-C-methyl-D-erythritol-4-phosphate

There are two distinct pathways for biosynthesis of the IPP and DMAPP the mevalonate (MVA) pathway and the DXP pathway (Figure 12.3). The MVA pathway functions primarily in eukaryotes, while the DXP pathway is typically present in prokaryotes and the plastids of plants [90,91]. The first reaction in the DXP pathway is the condensation of pyruvate and D-glyceraldehyde-3-phosphate (G3P) to form DXP, which is catalyzed by DXP synthase encoded by the gene dxs [92]. In the second step, DXP is reduced to 2-C-methyl-D-erythritol-4-phosphate (MEP) by DXP reductoisomerase, which is encoded by the gene dxr (ispC) in E. coli. An array of other enzymes encoded by is pi), ispE, ispF, ispG, and ispH act in subsequent sequential reactions, leading to the conversion of MEP to IPP and DMAPP, which are interconverted by the enzyme encoded by idi [93-97],... 

Figure 9.4 Monoterpene biosynthesis in peppermint oil gland secretory cells. The enzymes involved in this pathway are (1) 1-deoxy-D-xylulose 5-phosphate synthase, (2) 2-C-methyl-D-erythritol 4-phosphate reductoisomerase, (3) 2-C-methyl-D-erythritol 4-phosphate cytidyltransferase, (4) 4-(cytidine 5 -diphospho)-2-C-methyl-D-erythritol kinase, (5) 2-C-methyl-D-erythritol 2,4-cyclodiphosphate synthase, (6) isopentenyl diphosphate isomerase, (7) geranyl diphosphate synthase, (8)...

It had been suggested that the second step of the mevalonate-independent pathway involved an intramolecular rearrangement and subsequent reduction of DXP to yield 2-C-methyl-D-erythritol 4-phosphate (Fig. 9.6A).29-3 Seto and co-workers reported the isolation, by using a mutant complementation approach, and characterization of such a reductoisomerase gene from E. coli)2 Based on likely... 

TAKAHASHI, S., KUZUYAMA, T WATANABE H., SETO, H., A 1-deoxy-D-xylulose 5-phosphate reductoisomerase catalyzing the formation of 2-C-methyl-D-erythritol 4-phosphate in an alternative nonmevalonate pathway, Proc. Natl. Acad. Sci. USA, 1998, 95, 9879-9884. 

KUZUYAMA, T., TAKAGI, M., KANEDA, K., WATANABE, H., DAIRI, T., SETO, H., Formation of 4-(cytidine 5 -diphospho)-2-C-methyl-D-erythritol from 2-C-methyl-D-erythritol 4-phosphate by 2-C-methyl-D-erythritol 4-phosphate cytidyltransferase, a new enzyme in the nonmevalonate pathway, Tetrahedron Lett., 2000, 41, 703-706. 

The CPPase substrate DMAPP (15) is formed from isopentenyl pyrophosphate (IPP) (14) via the IPP isomerase reaction. It had been assumed that IPP was generated only via mevalonic acid (12) (Fig. 2), but Rohmer discovered another route, 2-C-methyl-D-erythritol 4-phosphate (13) (MEP) pathway (Fig. 2) [22, 23]. A key step in the MEP pathway is the reaction catalyzed by 1-deoxy-D-xylulose 5-phosphate synthase (DXS), which combines hydroxyethyl thiamine pyrophosphate (hydroxyethyl TPP) generated from pyruvic acid (17) and TPP with glyceral-dehyde 3-phosphate (18) to yield 1-deoxy-D-xylulose 5-phosphate (19) containing five carbons. The mevalonate pathway operates in the cytosol of plants and animals, whereas the MEP pathway is present in the plastid of plants or in eubacteria [24-27]. 

Fig. 2 Two possible biosynthetic pathways to pyrethrolone. The [l-13C]D-glucose-derived 13C labels that occur in the mevalonic acid and 2-C-methyl-D-erythritol 4-phosphate (13) pathways are colored in red and green, respectively. The phosphate moiety is indicated as P ...

Wanke M, Skorupinska-Tudek K, Swiezewska E (2001) Isoprenoid biosynthesis via 1-deoxy-D-xylulose 5-phosphate/2-C-methyl-D-erythritol 4-phosphate (DOXP/MEP) pathway. Act... 

Gerber E, Hemmerlin A, Hartmann M, Heintz D, Hartmann MA, Mutterer J, Rodriguez-Concepcion M, Boronat A, Van Dorsselaer A, Rohmer M, CroweU DN, Bach TJ (2009) The plastidial 2-C-methyl-D-erythritol 4-phosphate pathway provides the isoprenyl moiety for protein geranylgeranylation in tobacco BY-2 ceUs. Plant Cell 21 285-300... 

Figure 27 Four possible pathways for ABA biosynthesis. Open and closed circles show the 13C label from [1-13C]-d-glucose in the mevaloic acid pathway and the MEP pathway, respectively. DAP, dihydroxyacetone phosphate DXP, 1-deoxy-xylulose-5-phosphate FDP, farnesyl diphosphate GAP, glyceraldehyde-3-phosphate GGDP, geranylgeranyl diphosphate HMG-CoA, 3-hydroxy-3-methylglutaryl CoA IDP, isopentenyl diphosphate MEP, 2-C-methyl-D-erythritol-4-phosphate.

Figure 5.4 Outline of the newly discovered glyceraldehyde phosphate/pyruvate pathway for the formation of C5 isoprenoid units. None of the intermediates after 2-C-methyl-D-erythritol 4-phosphate is known. P indicates a phosphate moiety. TPP, thiamine pyrophosphate NADP, nicotinamide adenine dinucleotide phosphate.

Several coenzymes are involved in the biosynthesis of their own precursors. Thus, thiamine is the cofactor of the enzyme that converts 1-deoxy-D-xylulose 5-phosphate (43) (the precursor of thiamine pyrophosphate, pyridoxal 5 -phosphate and of iso-prenoids via the nomnevalonate pathway) into 2 C-methyl-D-erythritol 4-phosphate (90, Fig. 11). Similarly, two enzymes required for the biosynthesis of GTP, which is the precursor of tetrahydrofolate, require tetrahydrofolate derivatives as cofactors (Fig. 3). When a given coenzyme is involved in its own biosynthesis, we are faced with a hen and egg problem, namely how the biosynthesis could have evolved in the absence of the cmcially required final product. The answers to that question must remain speculative. The final product may have been formed via an alternative biosynthetic pathway that has been abandoned in later phases of evolution or that may persist in certain organisms but remains to be discovered. Alternatively, the coenzyme under study may have been accessible by a prebiotic sequence of spontaneous reactions. An interesting example in this respect is the biosynthesis of flavin coenzymes, in which several reaction steps can proceed without enzyme catalysis despite their mechanistic complexity. 

Fox DT, Poulter CD. Mechanistic studies with 2-C-methyl-D-erythritol 4-phosphate synthase from Escherichia coli. Biochemistry 2005 44 3860-3868. 

Steinbacher S, Kaiser J, Eisenreich W, Huber R, Bacher A, Rohdich F. Structural basis of fosmidomycin action revealed by the complex with 2-C-methyl-D-erythritol 4-phosphate synthase (IspC). J. Biol. Chem. 2003 278 18401-18407. 

Terpenoids are derived from the cytosolic mevalonate pathway or from the plastidial 2-C-methyl-D-erythritol-4-phosphate (MEP) pathway (see also Terpenoid Biosynthesis). Both pathways lead to the formation of the C5 units isopentenyl diphosphate and its allylic isomer dimethylallyl diphosphate, which are the basic terpenoid biosynthesis building blocks (Fig. 1). Although increasing evidence suggests that exchange of intermediates occurs between these compartments, the cytoplasmic mevalonate pathway is generally considered to supply the precursors for the production of sesquiterpenes and triterpenes (including sterols) and to provide precursors for protein prenylation and for ubiquinone and heme-A production in mitochondria. In the plastids, the MEP pathway supplies the precursors for the production of isoprene, monoterpenes, diterpenes (e.g., GAs), and tetraterpenes (e.g., carotenoids). 

R,4S)-3,4-Dihydroxy-5-oxohexylphosphonic acid (282), an isosteric analogue of l-deoxy-D-xylulose-5-phosphate (DXP), the first C5 intermediate in the MEP pathway for isoprenoid biosynthesis has been synthesized from (+)2,3-0-benzylidene-D-threitol (283) by a seven step reaction sequence. This phosphonate (282) was next enzymatically converted into (3R,4R)-3,4,5-trihy-droxyphosphonic acid (284), an isosteric analogue of 2-C-methyl-D-erythritol-4-phosphate (Scheme 72). 

The mechanism of UDP-galactopyranosyl transferase has been investigated using C-glycosidic UDP-Gal and amido derivatives (80) acting as transition state-based enzyme inhibitors. A similar transferase, the cytidylyltransferase, has been used to synthesise 4-(cytidine 5 -diphospho)-2-C-methyl-D-erythritol (81) from 2-C-methyl-D-erythritol 4-phosphate in the presence of CTP. ... 

Another recent example arises from the scrutiny of the 2-C-methyl-D-erythritol-4-phosphate pathway for isopre-noid biosynthesis where key enzyme is 1-deoxy-D-xylose 5-phosphate reductoisomerase (DXR). DXR have no functional equivalent in humans making it an attractive target for novel antimalarial, antibacterial and herbicidal agents. ... 

The enzyme 2-C-methyl-D-erythritol-4-phosphate synthetase appears to catalyse a Bilik reaction (Figure 6.10) the substrate l-deoxyxylulose-5-phosphate is converted to the title compound via an intermediate aldehyde, whose carbonyl derives from C3 of the substrate. The first step is thus a Bilik reaction and the aldehyde is subsequently reduced by the enzyme using NADPH as reductant, The X-ray crystal structure of the Escherichia coli enzyme in complex with the promising antimalarial Fosmidomycin (a hydroxamic acid) reveals a bound Mn " coordinated to oxygens equivalent to the substrate carbonyl and 03. The stereochemistry and regiochemistry follow the normal Bilik course, although the crystallographers favour an alkyl shift rather than a reverse aldol-aldol mechanism. The intermediate aldehyde has been shown to be a catalytically competent intermediate. 

Reaction catalysed by 2-C-methyl-D-erythritol-4-phosphate synthetase. The reaction is drawn with a metal-templated reverse aldol-aldol mechanism, rather than the alkyl shift mechanism. The prop-2-en-2,3-diolate is below the plane of the glycolaldehyde phosphate. 

ESTEVEZ, J. M., CANTERO, A., ROMERO, C., KAWAIDE, H., JIMENEZ, L, F., KUZUYAMA, T., SETO, H., KAMIYA, Y., LEON, P., Analysis of the expression of CLAl, a gene that encodes the 1- deoxyxylulose 5-phosphate synthase of the 2-C-methyl-D-erythritol-4- phosphate pathway in Arabidopsis., Plant Physiol. 2000,124, 95-104. 

CARRETERO-PAULET, L., AHUMADA, I., CUNILLERA, N., RODRIGUEZ-CONCEPCION, M., FERRER, A., BORONAT, A., CAMPOS, N., Expression and molecular analysis of the Arabidopsis DXR Gene encoding 1-deoxy-D-xylulose 5-phosphate reductoisomerase, the first committed enzyme of the 2-C-methyl-D-erythritol 4-phosphate pathway.,/Van/PAyi-io/. 2002,129, 1581-1591. 

C-Methyl-D-erythritol 4-phosphate (4), a key isoprenoid precursor in the mevalonate-independent pathway leading to isopentenyl diphosphate, has been synthesized in eight steps from 1,2-0-isopropylidene-a-D-xylofuranose in such a way as to facilitate the incorporation of C or radiolabels. Syntheses of the non-phosphorylated derivative, 5, and its L-threitol diastereomer, 6, from d-glucose and D-galactose respectively, have also been reported. 3p-(5 -D-Ribityl)cholestane (7), a putative biological precursor for fossil 3-alkylsteranes, has been synthesized from cholestanone by the stepwise and stereoselective construction and subsequent reductive opening of a 3p-(5 -deoxy-5 -yl-D-ribono-l,4-lactone) substituent/... 

The CDP-derivative 211 of 2-C-methyl-D-erythrito, an intermediate in the non-mevalonate pathway to isoprenoids, has been synthesized from 2-C-methyl-D-erythritol-4-phosphate and CTP, using the transferase which produces 211 naturally. " Enzymatic routes have also been used to produce 211 with multiple specific C-labels, and also 2- C-labelled material. ... 

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