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. 1986 Jun 15;236(3):917–919. doi: 10.1042/bj2360917

Hysteretic behaviour of carnitine palmitoyltransferase. The effect of preincubation with malonyl-CoA.

G A Cook, K A Cox
PMCID: PMC1146927  PMID: 3790097

Abstract

Continuous assays of carnitine palmitoyltransferase were used to study the hysteretic behaviour of the enzyme. When reactions were started by adding mitochondria to complete reaction mixtures, there was a lag in the assay even in the absence of malonyl-CoA. When mitochondria were preincubated with malonyl-CoA in the absence of palmitoyl-CoA, there was a greater lag period in the assay of carnitine palmitoyltransferase, but this lag was less prominent at 37 degrees C than at 30 degrees C. Preincubation of mitochondria with malonyl-CoA did not change the sensitivity of the enzyme to inhibition by malonyl-CoA.

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Selected References

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

  1. Cook G. A. Differences in the sensitivity of carnitine palmitoyltransferase to inhibition by malonyl-CoA are due to differences in Ki values. J Biol Chem. 1984 Oct 10;259(19):12030–12033. [PubMed] [Google Scholar]
  2. Cook G. A. Involvement of hysteretic effects in the inhibition of carnitine palmitoyltransferase by malonyl-CoA. Biochem J. 1984 Dec 15;224(3):1015–1018. doi: 10.1042/bj2241015. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Cook G. A., King M. T., Veech R. L. Ketogenesis and malonyl coenzyme A content of isolated rat hepatocytes. J Biol Chem. 1978 Apr 25;253(8):2529–2531. [PubMed] [Google Scholar]
  4. Cook G. A., Nielsen R. C., Hawkins R. A., Mehlman M. A., Lakshmanan M. R., Veech R. L. Effect of glucagon on hepatic malonyl coenzyme A concentration and on lipid synthesis. J Biol Chem. 1977 Jun 25;252(12):4421–4424. [PubMed] [Google Scholar]
  5. Cook G. A., Otto D. A., Cornell N. W. Differential inhibition of ketogenesis by malonyl-CoA in mitochondria from fed and starved rats. Biochem J. 1980 Dec 15;192(3):955–958. doi: 10.1042/bj1920955. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Gamble M. S., Cook G. A. Alteration of the apparent Ki of carnitine palmitoyltransferase for malonyl-CoA by the diabetic state and reversal by insulin. J Biol Chem. 1985 Aug 15;260(17):9516–9519. [PubMed] [Google Scholar]
  7. Harano Y., Kashiwagi A., Kojima H., Suzuki M., Hashimoto T., Shigeta Y. Phosphorylation of carnitine palmitoyltransferase and activation by glucagon in isolated rat hepatocytes. FEBS Lett. 1985 Sep 2;188(2):267–272. doi: 10.1016/0014-5793(85)80385-9. [DOI] [PubMed] [Google Scholar]
  8. Ontko J. A., Johns M. L. Evaluation of malonyl-CoA in the regulation of long-chain fatty acid oxidation in the liver. Evidence for an unidentified regulatory component of the system. Biochem J. 1980 Dec 15;192(3):959–962. doi: 10.1042/bj1920959. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Robinson I. N., Zammit V. A. Sensitivity of carnitine acyltransferase I to malonly-CoA inhibition in isolated rat liver mitochondria is quantitatively related to hepatic malonyl-CoA concentration in vivo. Biochem J. 1982 Jul 15;206(1):177–179. doi: 10.1042/bj2060177. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Saggerson E. D. Carnitine acyltransferase activities in rat liver and heart measured with palmitoyl-CoA and octanoyl-CoA. Latency, effects of K+, bivalent metal ions and malonyl-CoA. Biochem J. 1982 Feb 15;202(2):397–405. doi: 10.1042/bj2020397. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Zammit V. A. Effects of the mode of addition of acyl-CoA on the initial rate of formation of acylcarnitine in the presence of carnitine by intact rat liver mitochondria in vitro. Biochem J. 1985 Jul 1;229(1):273–275. doi: 10.1042/bj2290273. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Zammit V. A. Increased sensitivity of carnitine palmitoyltransferase I activity to malonyl-CoA inhibition after preincubation of intact rat liver mitochondria with micromolar concentrations of malonyl-CoA in vitro. Biochem J. 1983 Mar 15;210(3):953–956. doi: 10.1042/bj2100953. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Zammit V. A. Time-dependence of inhibition of carnitine palmitoyltransferase I by malonyl-CoA in mitochondria isolated from livers of fed or starved rats. Evidence for transition of the enzyme between states of low and high affinity for malonyl-CoA. Biochem J. 1984 Mar 1;218(2):379–386. doi: 10.1042/bj2180379. [DOI] [PMC free article] [PubMed] [Google Scholar]

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