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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
Article

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).

Key words

control coefficients logarithmic gains pentose phosphate 

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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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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