Deoxyxylulose 5-phosphate

The terpenoid precursor isopentenyl diphosphate, formerly called isopentenyl pyrophosphate and abbreviated IPP, is biosynthesized by two different pathways depending on the organism and the structure of the final product. In animals and higher plants, sesquiterpenoids and triterpenoids arise primarily from the mevalonate pathway, whereas monoterpenoids, diterpenoids, and tetraterpenoids are biosynthesized by the 1-deoxyxylulose 5-phosphate (DXP) pathway. In bacteria,... 

Sprenger, G.A. et al.. Identification of a thiamin-dependent synthase in Escherichia coli required for the formation of the 1-deoxy-D-xylulose 5-phosphate precursor to isoprenoids, thiamin, and pyridoxol, Proc. Natl. Acad Sci. USA 94, 12857, 1997. Lange, B.M. et al., A family of transketolases that directs isoprenoid biosynthesis via a mevalonate-independent pathway, Proc. Natl. Acad Sci. USA 95, 2100, 1998. Lois, L.M. et al., Cloning and characterization of a gene from Escherichia coli encoding a transketolase-like enzyme that catalyzes the synthesis of D-1- deoxyxylulose 5-phosphate, a common precursor for isoprenoid, thiamin, and pyridoxol biosynthesis, Proc. Natl. Acad. Sci. USA 95, 2105, 1998. 

Schoenwaelder MEA (2002) Physode distribution and the effect of thallus sunburn in Flormosira banksii (Fucales, Phaeophyceae). Bot Mar 45 262-266 Schoenwaelder MEA, Clayton MN (2000) Physode formation in embryos of Phyllospora comosa and Flormosira banksii (Phaeophyceae). Phycologia 39 1-9 Schwender J, Gemunden C, Lichtenthaler HK (2001) Chlorophyta exclusively use the 1-deoxyxylulose 5-phosphate/2-C-methylerythritol 4-phosphate pathway for the biosynthesis of isoprenoids. Planta 212 416 123... 

Alkaloid biosynthesis needs the substrate. Substrates are derivatives of the secondary metabolism building blocks the acetyl coenzyme A (acetyl-CoA), shikimic acid, mevalonic acid and 1-deoxyxylulose 5-phosphate (Figure 21). The synthesis of alkaloids starts from the acetate, shikimate, mevalonate and deoxyxylulose pathways. The acetyl coenzyme A pathway (acetate pathway) is the source of some alkaloids and their precursors (e.g., piperidine alkaloids or anthraniUc acid as aromatized CoA ester (antraniloyl-CoA)). Shikimic acid is a product of the glycolytic and pentose phosphate pathways, a construction facilitated by parts of phosphoenolpyruvate and erythrose 4-phosphate (Figure 21). The shikimic acid pathway is the source of such alkaloids as quinazoline, quinoline and acridine. 

Other ThDP enzymes catalyze the formation of C-C bonds by transferring C2 units from a donor compound to an acceptor compound (transferase activity). We have studied the E. coli transketolase with respect to structure-function relationships, as well as to possible applications in asymmetric syntheses (Section 2.2.2.2.1). During the late 1990s a transketolase-like enzyme, 1-deoxyxylulose 5-phosphate synthase, was discovered. Its structure and value in chemoenzymatic syntheses were also assessed in project B21 (Section 2.2.2.2.2). 

Thiamin is synthesized in bacteria, fungi, and plants from 1-deoxyxylulose 5-phosphate (Eq. 25-21), which is also an intermediate in the nonmevalonate pathway of polyprenyl synthesis. However, thiamin diphosphate is a coenzyme for synthesis of this intermediate (p. 736), suggesting that an alternative pathway must also exist. Each of the two rings of thiamin is formed separately as the esters 4-amino-5-hydroxy-methylpyrimidine diphosphate and 4-methyl-5-((i-hydroxyethyl) thiazole monophosphate. These precursors are joined with displacement of pyrophosphate to form thiamin monophosphate.92b In eukaryotes this is hydrolyzed to thiamin, then converted to thiamin diphosphate by transfer of a diphospho group from ATP.92b c In bacteria thiamin monophosphate is converted to the diphosphate by ATP and thiamin monophosphate kinase.92b... 

Deoxyhemerythrin, oxygenation of 862 Deoxyhemoglobin 850, 851 Deoxy-D-mannooctulosonic acid (KDO) 180s Deoxyribonuclease 652 - 653 Deoxyribonucleic acid. See DNA 2-Deoxyribose 200s 1-Deoxyxylulose 5-phosphate 735, 736 Dephosphorylation, cascade 542 Depsides 23 Depsipeptide 414... 

The pathway also operates in some bacteria and apparently is the sole source of isoprenoid compounds for the unicellular alga Scenedesmus.28 The pathway is outlined in Fig. 22-2. Pyruvate is decarboxylated by a thiamin diphosphate-dependent enzyme,29 and the resulting enamine is condensed with D-glyceraldehyde 3-phosphate to form 1-deoxyxylulose 5-phosphate.28, i0 31a The latter undergoes an isomeroreductase rearrange-... 

Figure 22-2 The glyceraldehyde 3-phosphate pyruvate alternative pathway of isoprenoid biosynthesis. The intermediate 1-deoxyxylulose 5-phosphate may enter terpenes, vitamin B6, and thiamin. Isopentenyl diphosphate is shown as the final product, but the intermediate steps are uncertain. See Lange et al 2 ...

The thiazole ring is assembled on the 5-carbon backbone of 1-deoxyxylulose 5-phosphate, which is also an intermediate in the alternative biosynthetic pathway for terpenes (Fig. 22-2) and in synthesis of vitamin B6 (Fig. 25-21). In E. coli the sulfur atom of the thiazole comes from cysteine and the nitrogen from tyrosine.374 The same is true for chloroplasts,375 whereas in yeast glycine appears to donate the nitrogen.372 The thiamin biosynthetic operon of E. coli contains six genes,372a 376 one of which (ThiS) encodes a protein that serves as a sulfur carrier from cysteine into the thiazole.374 The C-terminal glycine is converted into a thiocarboxylate ... 

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. 

R 274 W. Eisenreich, F. Rohdich and A. Bacher, Isopentenyl Diphosphate Biosynthesis via 1-Deoxyxylulose 5-Phosphate , p. 133... 

Figure 3.6 The biosynthesis of IPP and DMAPP from 1 -deoxyxylulose 5-phosphate.

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