If an enzyme name is shown in bold, there is experimental evidence for this enzymatic activity.
Synonyms: pentose shunt, hexose monophosphate shunt, phosphogluconate pathway, superpathway of oxidative and non-oxidative branches of pentose phosphate pathway
|Superclasses:||Generation of Precursor Metabolites and Energy → Pentose Phosphate Pathways|
The pentose phosphate pathway is an alternative way of oxidizing glucose, and in this pathway the oxidation is coupled to NADPH synthesis. As a result, the pentose phosphate pathway is a major source of reducing equivalents for biosynthesis reactions. The pentose phosphate pathway is also important for the conversion of hexoses to pentoses [Zubay83] .
About This Pathway
The pentose phosphate pathway is one of the three essential pathways of central metabolism. It supplies three of Escherichia coli's 13 precursor metabolites (compounds needed for the biosyntheses): D-ribose 5-phosphate, D-sedoheptulose 7-phosphate, and D-erythrose 4-phosphate. Regardless of the carbon source upon which Escherichia coli is growing, some carbon must flow through the pentose phosphate pathway to meet the cell's requirements for these metabolites. In addition this pathway is an important source of NADPH, which is also needed for biosyntheses. The pathway begins with one intermediate of glycolysis, β-D-glucose 6-phosphate, and ends with the formation of two others, β-D-fructofuranose 6-phosphate and D-glyceraldehyde 3-phosphate.
For convenience, the pentose phosphate pathway is commonly divided into its preliminary oxidative portion, in which β-D-glucose 6-phosphate is oxidized to D-ribulose 5-phosphate, and its subsequent non-oxidative portion in which through a series of transaldolase and transketolase reactions, D-ribulose 5-phosphate is converted into β-D-fructofuranose 6-phosphate and D-glyceraldehyde 3-phosphate.
Superpathways: superpathway of glucose and xylose degradation
Variants: pentose phosphate pathway (partial)
Acebron09: Acebron SP, Martin I, del Castillo U, Moro F, Muga A (2009). "DnaK-mediated association of ClpB to protein aggregates. A bichaperone network at the aggregate surface." FEBS Lett 583(18);2991-6. PMID: 19698713
Asztalos07: Asztalos P, Parthier C, Golbik R, Kleinschmidt M, Hubner G, Weiss MS, Friedemann R, Wille G, Tittmann K (2007). "Strain and near attack conformers in enzymic thiamin catalysis: X-ray crystallographic snapshots of bacterial transketolase in covalent complex with donor ketoses xylulose 5-phosphate and fructose 6-phosphate, and in noncovalent complex with acceptor aldose ribose 5-phosphate." Biochemistry 46(43);12037-52. PMID: 17914867
Aucamp08: Aucamp JP, Martinez-Torres RJ, Hibbert EG, Dalby PA (2008). "A microplate-based evaluation of complex denaturation pathways: structural stability of Escherichia coli transketolase." Biotechnol Bioeng 99(6);1303-10. PMID: 17969139
Beutler85: Beutler E, Kuhl W, Gelbart T (1985). "6-Phosphogluconolactonase deficiency, a hereditary erythrocyte enzyme deficiency: possible interaction with glucose-6-phosphate dehydrogenase deficiency." Proc Natl Acad Sci U S A 82(11);3876-8. PMID: 3858849
Butland05: Butland G, Peregrin-Alvarez JM, Li J, Yang W, Yang X, Canadien V, Starostine A, Richards D, Beattie B, Krogan N, Davey M, Parkinson J, Greenblatt J, Emili A (2005). "Interaction network containing conserved and essential protein complexes in Escherichia coli." Nature 433(7025);531-7. PMID: 15690043
Chandran03: Chandran SS, Yi J, Draths KM, von Daeniken R, Weber W, Frost JW (2003). "Phosphoenolpyruvate availability and the biosynthesis of shikimic acid." Biotechnol Prog 19(3);808-14. PMID: 12790643
Chang95d: Chang JT, Green CB, Wolf RE (1995). "Inhibition of translation initiation on Escherichia coli gnd mRNA by formation of a long-range secondary structure involving the ribosome binding site and the internal complementary sequence." J Bacteriol 177(22);6560-7. PMID: 7592434
Chen10d: Chen YY, Ko TP, Chen WH, Lo LP, Lin CH, Wang AH (2010). "Conformational changes associated with cofactor/substrate binding of 6-phosphogluconate dehydrogenase from Escherichia coli and Klebsiella pneumoniae: Implications for enzyme mechanism." J Struct Biol 169(1);25-35. PMID: 19686854
Chistoserdova00: Chistoserdova L, Gomelsky L, Vorholt JA, Gomelsky M, Tsygankov YD, Lidstrom ME (2000). "Analysis of two formaldehyde oxidation pathways in Methylobacillus flagellatus KT, a ribulose monophosphate cycle methylotroph." Microbiology 146 ( Pt 1);233-8. PMID: 10658669
Collard99: Collard F, Collet JF, Gerin I, Veiga-da-Cunha M, Van Schaftingen E (1999). "Identification of the cDNA encoding human 6-phosphogluconolactonase, the enzyme catalyzing the second step of the pentose phosphate pathway(1)." FEBS Lett 459(2);223-6. PMID: 10518023
David70: David J, Wiesmeyer H (1970). "Regulation of ribose metabolism in Escherichia coli. II. Evidence for two ribose-5-phosphate isomerase activities." Biochim Biophys Acta 208(1);56-67. PMID: 4909663
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