A model of the pentose phosphate pathway in rat liver cells

Abstract

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).

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Abbreviations

GK:

Glucokinase, (E.C. 2.7.1.2.)

G6PDH:

D-glucose-6-phosphate dehydrogenase, (E.C. 1.1.1.49)

PLase:

6-Phosphogluconelactonase, (E.C. 3.1.1.31.)

PGIcDH:

6-Phosphogluconate dehydrogenase, (E.C. 1.1.1.44)

RPI:

D-ribose-5-phosphate keto-isomerase, (E.C. 5.3.1.6)

TK:

D-sedoheptulose-7-phosphate: D-glyceraldehyde-3-phosphate glycol-aldehyde transferase, (E.C. 2.2.1.1.)

TA:

D-sedoheptulose-7-phosphate: D-glyceraldehyde-3-phosphate dihydroxyacetone transferase, (E.C. 2.2.1.2)

EP:

D-ribulose-5-phosphate-3′-epimerase, (E.C. 5.1.3.1)

PGI:

D-glucose-6-phosphate keto-isomerase, (E.C. 5.3.1.9)

TPI:

D-glyceraldehyde-3-phosphate keto-isomerase, (E.C.5.3.1.1)

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Correspondence to Marta Cascante.

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Sabate, L., Franco, R., Canela, E.I. et al. A model of the pentose phosphate pathway in rat liver cells. Mol Cell Biochem 142, 9–17 (1995). https://doi.org/10.1007/BF00928908

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Key words

  • control coefficients
  • logarithmic gains
  • pentose phosphate