Skip to main content
NCBI home page
Biochemical Journal logoLink to Biochemical Journal
. 1978 Apr 1;171(1):215–223. doi: 10.1042/bj1710215

Pressure relaxation of the equilibrium of the pig heart lactate dehydrogenase system.

M J Hardman, J H Coates, H Gutfreund
PMCID: PMC1184150  PMID: 25657

Abstract

The relaxation behaviour of a system of reactants equilibrated in the presence of pig heart lactate dehydrogenase was studied after pressure perturbation. Two relaxations were observed when protein fluorescence was recorded, but only the slower relaxation was apparent in observations of A340. The faster relaxation therefore involves transfer between free and enzyme-bound NADH, whereas the slower relaxation represents the reduction of NAD+. Both relaxations were observed in Tris buffer, where there is little effect of pressure on pH, and in phosphate buffer, where pH changes are significant; however, the amplitudes depended on the buffer used. The slower reciprocal relaxation time increases with increasing total enzyme concentration and decreases slightly with increasing NAD+ concentration. Computer simulations, based on a proposed mechanism, were compared with the experimentally determined amplitudes and relaxation times as a test of the mechanism.

Full text

PDF
215

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Bagshaw C. R., Eccleston J. F., Eckstein F., Goody R. S., Gutfreund H., Trentham D. R. The magnesium ion-dependent adenosine triphosphatase of myosin. Two-step processes of adenosine triphosphate association and adenosine diphosphate dissociation. Biochem J. 1974 Aug;141(2):351–364. doi: 10.1042/bj1410351. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Boland M. J., Gutfreund H. Pig heart lactate dehydrogenase. Binding of pyruvate and the interconversion of pyruvate-containing ternary complexes. Biochem J. 1975 Dec;151(3):715–727. doi: 10.1042/bj1510715. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Davis J. S., Gutfreund H. The scope of moderate pressure changes for kinetic and equilibrium studies of biochemical systems. FEBS Lett. 1976 Dec 31;72(2):199–207. doi: 10.1016/0014-5793(76)80971-4. [DOI] [PubMed] [Google Scholar]
  4. Holbrook J. J., Gutfreund H. Approaches to the study of enzyme mechanisms lactate dehydrogenase. FEBS Lett. 1973 Apr 15;31(2):157–169. doi: 10.1016/0014-5793(73)80095-x. [DOI] [PubMed] [Google Scholar]
  5. Holbrook J. J., Gutfreund H., Südi J. Kinetic analysis of experiments involving the single turnover of an enzyme. Biochem J. 1976 Jul 1;157(1):287–288. doi: 10.1042/bj1570287. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Holbrook J. J. Protein fluorescence of lactate dehydrogenase. Biochem J. 1972 Jul;128(4):921–931. doi: 10.1042/bj1280921. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Schwert G. W., Miller B. R., Peanasky R. J. Lactic dehydrogenase. X. A re-evaluation of the effects of pH upon the kinetics of the reaction. J Biol Chem. 1967 Jul 25;242(14):3245–3252. [PubMed] [Google Scholar]
  8. Whitaker J. R., Yates D. W., Bennett N. G., Holbrook J. J., Gutfreund H. The identification of intermediates in the reaction of pig heart lactate dehydrogenase with its substrates. Biochem J. 1974 Jun;139(3):677–697. doi: 10.1042/bj1390677. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from Biochemical Journal are provided here courtesy of The Biochemical Society

RESOURCES