Biochemistry (Moscow)

, Volume 76, Issue 4, pp 491–492 | Cite as

Quasi-equilibrium assumption for arbitrary mechanism of enzymatic reaction. criteria for existence of equilibrium segments

  • P. V. VrzheshchEmail author


The possible application of the quasi-equilibrium assumption for an arbitrary mechanism of enzymatic reaction is considered. It is shown at what ratios of kinetic constants a segment consisting of two, three, and four intermediates may be considered as an equilibrium one. Expressions for evaluation of accuracy of distribution of intermediate concentrations inside the equilibrium segment and accuracy of determination of intermediate concentrations inside and outside the equilibrium segment as a function of the ratio of kinetic constants are derived. A method for determination of the limitations on the ratio of rate constants for an equilibrium segment of arbitrary structure is suggested.

Key words

enzyme kinetics quasi-equilibrium assumption accuracy of assumption Cha method rapid equilibrium steady-state kinetics graph method 


  1. 1.
    Cha, S. (1968) J. Biol. Chem., 243, 820–825.PubMedGoogle Scholar
  2. 2.
    Varon, R., Garcia-Moreno, M., Garrido, C., and Garcia-Canovas, F. (1992) Biochem. J., 288, 1072–1073.PubMedGoogle Scholar
  3. 3.
    Segel, I. H., and Martin, R. L. (1988) J. Theor. Biol., 135, 445–453.PubMedCrossRefGoogle Scholar
  4. 4.
    Topham, C. M., and Brocklehurst, K. (1992) Biochem. J., 282, 261–265.PubMedGoogle Scholar
  5. 5.
    Selwyn, M. J. (1993) Biochem. J., 295, 897–898.PubMedGoogle Scholar
  6. 6.
    Brocklehurst, K., and Topham, C. M. (1993) Biochem. J., 295, 897–898.Google Scholar
  7. 7.
    Vrzheshch, P. V. (2008) Biochemistry (Moscow), 73, 1114–1120.CrossRefGoogle Scholar
  8. 8.
    Vrzheshch, P. V. (2010) Biochemistry (Moscow), 75, 1374–1382.CrossRefGoogle Scholar

Copyright information

© Pleiades Publishing, Ltd. 2011

Authors and Affiliations

  1. 1.Department of Bioengineering and BioinformaticsLomonosov Moscow State UniversityMoscowRussia
  2. 2.International Biotechnological CenterLomonosov Moscow State UniversityMoscowRussia

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