Molecular and Cellular Biochemistry

, Volume 142, Issue 1, pp 9–17 | Cite as

A model of the pentose phosphate pathway in rat liver cells

  • Llorenç Sabate
  • Rafael Franco
  • Enric I. Canela
  • Josep J. Centelles
  • Marta Cascante


A mathematical model based on kinetic data taken from the literature is presented for the pentose phosphate pathway in fasted rat liver steady-state. Since the oxidative and non oxidative pentose phosphate pathway can act independently, the complete (oxidative + non oxidative) and the non oxidative pentose pathway were simulated.

Sensitivity analyses are reported which show that the fluxes are mainly regulated by D-glucose-6-phosphate dehydrogenase (for the oxidative pathway) and by transketolase (for the non oxidative pathway). The most influent metabolites were the group ATP, ADP, P1 and the group NADPH, NADP+ (for the non oxidative pathway).

Key words

control coefficients logarithmic gains pentose phosphate 



Glucokinase, (E.C.


D-glucose-6-phosphate dehydrogenase, (E.C.


6-Phosphogluconelactonase, (E.C.


6-Phosphogluconate dehydrogenase, (E.C.


D-ribose-5-phosphate keto-isomerase, (E.C.


D-sedoheptulose-7-phosphate: D-glyceraldehyde-3-phosphate glycol-aldehyde transferase, (E.C.


D-sedoheptulose-7-phosphate: D-glyceraldehyde-3-phosphate dihydroxyacetone transferase, (E.C.


D-ribulose-5-phosphate-3′-epimerase, (E.C.


D-glucose-6-phosphate keto-isomerase, (E.C.


D-glyceraldehyde-3-phosphate keto-isomerase, (E.C.


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  1. 1.
    Kanji MI, Tows ML, Carper WR: A kinetic study of glucose-6-phosphate dehydrogenase. J Biol Chem 251: 2258–2262, 1976Google Scholar
  2. 2.
    Bauer HP, Srihari T, Jochims JT, Hofer HW: 6-Phosphogluconolactonase. Purification, properties and activities in various tissues. Eur J Biochem 133: 163–168, 1983Google Scholar
  3. 3.
    Schofield PJ, Sols A: Rat liver 6-phosphogluconolactonase: a low Km enzyme. Biochem Biophys Res Commun 71: 1313–1319, 1976Google Scholar
  4. 4.
    Villet RH, Dalziel K: Studies of 6-phosphogluconate dehydrogenase from sheep liver. I. Kinetics of the reductive carboxylation reaction. Eur J Biochem 27: 244–250, 1972Google Scholar
  5. 5.
    Toews ML, Kanji MI, Carper WR: 6-Phosphogluconate dehydrogenase. Purification and kinetics. J Biol Chem 251: 7127–7131, 1976Google Scholar
  6. 6.
    Topham CM, Dalziel K: The chemical mechanism of sheep liver 6-phosphogluconate dehydrogenase. A Schiff-base intermediate is not involved. Biochem J 234: 671–677, 1986Google Scholar
  7. 7.
    Gerber G, Preissler H, Heinrich R, Rapoport SM: Hexokinase of human erythrocytes. Purification, kinetic model, and its application to the conditions in the cell. Eur J Biochem 45: 39–52, 1974Google Scholar
  8. 8.
    Kiely ME, Stuart AL, Wood T: Partial purification and kinetic properties of ribose 5-phosphate ketol-isomerase and ribulose 5-phosphate 3-epimerase from various sources. Biochim Biophy Acta 293: 534–541, 1973Google Scholar
  9. 9.
    Dobrogosz WJ, Demoss RD: Studies on the regulation of ribosephosphateisomerase activity inPediococcus pentosaceus. Biochim Biophys Acta 77: 629–638, 1963Google Scholar
  10. 10.
    Domagk GF, Alexander WR: In: WA Wood (ed.). Methods in Enzymology vol. 41. Academic Press, New York, 1975, pp 424–426Google Scholar
  11. 11.
    Urivetzky M, Tsuboi KK: Enzymes of the human erythrocyte. V. Pentose phosphate isomerase, purification and properties. Arch Biochem Biophys 103: 1–8, 1963Google Scholar
  12. 12.
    McIntyre LM, Thorburn DR, Bubb WA, Kuchel PW: Comparison of computer simulations of the F-type and L-type non-oxidative hexose monophosphate shunts with31P-NMR experimental data from human erythrocytes. Eur J Biochem 180: 399–420, 1989Google Scholar
  13. 13.
    Wood T: The preparation of transketolase free from D-ribulose-5-phosphate 3-epimerase. Biochim Biophys Acta 659: 233–243, 1981Google Scholar
  14. 14.
    Canela EI: A program for deriving rate-equations using small computers. Int Biomed Compt 14: 43–52, 1983Google Scholar
  15. 15.
    Wood T: The Pentose Phosphate Pathway. Academic Press, Inc. London, 1985Google Scholar
  16. 16.
    Novello F, McLean P: The pentose phosphate pathway of glucose metabolism. Measurement of the non-oxidative reactions of the cycle. Biochem J 107: 775–791, 1968Google Scholar
  17. 17.
    Ljungdahl L, Wood HG, Racker E, Couri D: Formation of unequally labeled fructose 6-phosphate by an exchange reaction catalyzed by transaldolase. J Biol Chem 236: 1622–1630, 1961Google Scholar
  18. 18.
    Horecker BL, Smyrniotis PZ: Purification and properties of yeast transaldolase. J Biol Chem 212: 811–855, 1955Google Scholar
  19. 19.
    Kuhn E, Brand K: Purification and properties of transaldolase from bovine mammary gland. Biochemistry 11: 1767–1722, 1972Google Scholar
  20. 20.
    Hurwitz J, Horecker BL: The purification of phosphoketopentoepimerase fromLactobacillus pentosus and the preparation of xylulose 5-phosphate. J Biol Chem 223: 993–1008, 1956Google Scholar
  21. 21.
    Tsolas O, Horecker BL: In P. Boyer (ed.) The Enzymes ‘Transaldolase’, Vol. 7 1972Google Scholar
  22. 22.
    Wood T: Purification and properties of D-ribulose-5-phosphate 3-epimerase from calf liver. Biochim Biophys Acta 570: 352–362, 1979Google Scholar
  23. 23.
    Kauffman FC: Quantitative histochemistry of enzymes of the pentose phosphate pathway in the central nervous system of the rat. J Neurochem 19: 1–9, 1972Google Scholar
  24. 24.
    Kahana SE, Lowry OH, Schulz DW, Passoneau JV, Crawford EJ: The kinetics of phosphoglucoisomerase. J Biol Chem 235: 2178–2181, 1960Google Scholar
  25. 25.
    Lee EW, Barriso JA, Pepe M, Snyder R: Purification and properties of liver triose phosphate isomerase. Biochim Biophys Acta 242: 261–267, 1971Google Scholar

Copyright information

© Kluwer Academic Publishers 1995

Authors and Affiliations

  • Llorenç Sabate
    • 1
  • Rafael Franco
    • 1
  • Enric I. Canela
    • 1
  • Josep J. Centelles
    • 1
  • Marta Cascante
    • 1
  1. 1.Department de Bioquímica i Fisiologia, Facultat de QuímicaUniversitat de BarcelonaBarcelonaSpain

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