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. 1978 Dec 15;176(3):837–844. doi: 10.1042/bj1760837

The effects of ammonium chloride and bicarbonate on the activity of glutaminase in isolated liver mitochondria.

S K Joseph, J D McGivan
PMCID: PMC1186307  PMID: 747656

Abstract

1. Glutamine hydrolysis in liver mitochondria was studied by measuring the production of glutamate under conditions where this compound could not be further metabolized. 2. Glutaminase activity in intact mitochondria was very low in the absence of activators. 3. Glutamine hydrolysis was markedly stimulated by NH4Cl and also by HCO3- ions. 4. The stimulation by each of these compounds was much decreased if the mitochondria were uncoupled. 5. Maximum rates of glutamine hydrolysis required the addition of phosphate. A correlation was observed between the activity of glutaminase in the presence of NH4Cl plus HCO3- and the intramitochondrial content of ATP. 6. In disrupted mitochondria, NH4Cl stimulated glutaminase to a much smaller extent than in intact mitochondria. The NH4Cl stimulation in disrupted mitochondria was much increased by the addition of ATP. KHCO3 also stimulated glutaminase activity in disrupted mitochondria, and ATP increased the magnitude of this stimulation. 7. It was concluded that maximum rates of glutaminase activity in liver mitochondria require the presence of phosphate, ATP and either HCO3- or NH4+. A comparison of the results obtained on intact and broken mitochondria indicates that these effectors have a direct effect on the glutaminase enzyme system rather than an indirect effect mediated by changes in transmembrane ion gradients or in the concentrations of intramitochondrial metabolites.

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Selected References

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

  1. Adam P. A., Haynes R. C., Jr Control of hepatic mitochondrial CO2 fixation by glucagon, epinephrine, and cortisol. J Biol Chem. 1969 Dec 10;244(23):6444–6450. [PubMed] [Google Scholar]
  2. Blackburn E. H., Hird F. J., Jones I. K. Metabolism of glutamine and ammonia in rat liver: the effects of N-acetylglutamate and phosphate. Arch Biochem Biophys. 1972 Sep;152(1):265–271. doi: 10.1016/0003-9861(72)90214-7. [DOI] [PubMed] [Google Scholar]
  3. Cooper A. J., Meister A. The glutamine transaminase-omega-amidase pathway. CRC Crit Rev Biochem. 1977;4(3):281–303. doi: 10.3109/10409237709102560. [DOI] [PubMed] [Google Scholar]
  4. Crompton M., Chappell J. B. Transport of glutamine and glutamate in kidney mitochondria in relation to glutamine deamidation. Biochem J. 1973 Jan;132(1):35–46. doi: 10.1042/bj1320035. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Curthoys N. P., Kuhlenschmidt T. Phosphate-independent glutaminase from rat kidney. Partial purification and identity with gamma-glutamyltranspeptidase. J Biol Chem. 1975 Mar 25;250(6):2099–2105. [PubMed] [Google Scholar]
  6. Hird F. J., Marginson M. A. The formation of ammonia from glutamine and glutamate by mitochondria from rat liver and kidney. Arch Biochem Biophys. 1968 Sep 20;127(1):718–724. doi: 10.1016/0003-9861(68)90282-8. [DOI] [PubMed] [Google Scholar]
  7. Huang Y. Z., Knox W. E. A comparative study of glytaminase isozymes in rat tissues. Enzyme. 1976;21(5):408–426. doi: 10.1159/000458890. [DOI] [PubMed] [Google Scholar]
  8. Ishikawa E. The regulation of uptake and output of amino acids by rat tissues. Adv Enzyme Regul. 1976;14:117–136. doi: 10.1016/0065-2571(76)90010-8. [DOI] [PubMed] [Google Scholar]
  9. Joseph S. K., McGivan J. D. The effect of ammonium chloride and glucagon on the metabolism of glutamine in isolated liver cells from starved rats. Biochim Biophys Acta. 1978 Sep 21;543(1):16–28. doi: 10.1016/0304-4165(78)90450-6. [DOI] [PubMed] [Google Scholar]
  10. Kalra J., Brosnan J. T. Localization of glutaminase in rat liver. FEBS Lett. 1973 Dec 1;37(2):325–328. doi: 10.1016/0014-5793(73)80488-0. [DOI] [PubMed] [Google Scholar]
  11. Katunuma N., Huzino A., Tomino I. Organ specific control of glutamine metabolism. Adv Enzyme Regul. 1967;5:55–69. doi: 10.1016/0065-2571(67)90008-8. [DOI] [PubMed] [Google Scholar]
  12. Katunuma N., Tomino I., Nishino H. Glutaminase isozymes in rat kidney. Biochem Biophys Res Commun. 1966 Feb 3;22(3):321–328. doi: 10.1016/0006-291x(66)90485-2. [DOI] [PubMed] [Google Scholar]
  13. Kovacević Z., McGivan J. D., Chappell J. B. Conditions for activity of glutaminase in kidney mitochondria. Biochem J. 1970 Jun;118(2):265–274. doi: 10.1042/bj1180265. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Krebs H. A. Metabolism of amino-acids: The synthesis of glutamine from glutamic acid and ammonia, and the enzymic hydrolysis of glutamine in animal tissues. Biochem J. 1935 Aug;29(8):1951–1969. doi: 10.1042/bj0291951. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Lund P. Control of glutamine synthesis in rat liver. Biochem J. 1971 Sep;124(3):653–660. doi: 10.1042/bj1240653. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. McGivan J. D., Bradford N. M., Beavis A. D. Factors influencing the activity of ornithine aminotransferase in isolated rat liver mitochondria. Biochem J. 1977 Jan 15;162(1):147–156. doi: 10.1042/bj1620147. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. McGivan J. D., Bradford N. M., Mendes-Mourão J. The regulation of carbamoyl phosphate synthase activity in rat liver mitochondria. Biochem J. 1976 Feb 15;154(2):415–421. doi: 10.1042/bj1540415. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Stanley P. E., Williams S. G. Use of the liquid scintillation spectrometer for determining adenosine triphosphate by the luciferase enzyme. Anal Biochem. 1969 Jun;29(3):381–392. doi: 10.1016/0003-2697(69)90323-6. [DOI] [PubMed] [Google Scholar]
  19. Tate S. S., Meister A. Identity of maleate-stimulated glutaminase with gamma-glutamyl transpeptidase in rat kidney. J Biol Chem. 1975 Jun 25;250(12):4619–4627. [PubMed] [Google Scholar]
  20. Weil-Malherbe H. Activators and inhibitors of brain glutaminase. J Neurochem. 1969 Jun;16(3):855–864. doi: 10.1111/j.1471-4159.1969.tb08973.x. [DOI] [PubMed] [Google Scholar]
  21. Yamazaki R. K., Graetz G. S. Glucagon stimulation of citrulline formation in isolated hepatic mitochondria. Arch Biochem Biophys. 1977 Jan 15;178(1):19–25. doi: 10.1016/0003-9861(77)90166-7. [DOI] [PubMed] [Google Scholar]

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