Abstract
Acetylcarnitine was rapidly oxidised by pea mitochondria. (-)-carnitine was an essential addition for the oxidation of acetate or acetyl CoA. When acetate was sole substrate, ATP and Mg2+ were also essential additives for maximum oxidation. CoASH additions inhibited the oxidation of acetate, acetyl CoA and acetylcarnitine. It was shown that CoASH was acting as a competitive inhibitor of the carnitine stimulated O2 uptake. It is suggested that acetylcarnitine and carnitine passed through the mitochondrial membrane barrier with ease but acetyl CoA and CoA did not. Carnitine may also buffer the extra- and intra-mitochondrial pools of CoA. The presence of carnitine acetyltransferase (EC 2.3.1.7) on the pea mitochondria is inferred.
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Bonner, W.D. Jr. (1973) Mitochondria and plant respiration. In: Phytochemistry, vol. III, pp. 221–261, Miller, L.P., ed. Van Nostrand Rheinhold Co., New York
Chance, B. (1959) Quantitative aspects of the control of oxygen utilization. In: Ciba foundation symposium on regulation of cell metabolism, pp. 91–129. Wolstenhome, G.E.W., O'Conner, C.M., eds. Churchill, London
Chance, B., Williams, G.R. (1956) The respiratory chain and oxidative phosphorylation. Adv. Enzymol.17, 65–129
Edwards, Y.H., Chase, J.F.A., Edwards, M.R., Tubbs, P.K. (1974) Carnitine acetyltransferase: the question of multiple forms. Eur. J. Biochem.46, 209–215
Frenkel, R.A., McGarry, J.D. (1980) Conference on carnitine biosynthesis, metabolism and functions, University of Texas at Dallas, 1979 Carnitine biosynthesis, metabolism and functions. Frenkel, R.A., McGarry, J.D., eds. Academic Press, New York
Fritz, I.B. (1963) Carnitine and its role in fatty acid metabolism. Adv. Lipid. Res.1, 285–334
Lowry, O.H., Roseborough, N.J., Farr, A.L., Randall, R.J. (1951) Protein measurement with the Folin phenol reagent. J. Biol. Chem.193, 265–275
McNeil, P.H., Thomas, D.R. (1975) Carnitine content of pea seedling cotyledons. Phytochemistry14, 2335–2336
McNeil, P.H., Thomas, D.R. (1976) The effect of carnitine on palmitate oxidation by pea cotyledon mitochondria. J. Exp. Bot.27, 1163–1180
Pande, S.V. (1975) A mitochondrial carnitine acylcarnitine translocase system. Proc. Natl. Acad. Sci. USA72, 883–887
Pande, S.V., Parvin, R. (1976) Characterisation of carnitine acylcarnitine translocase system of heart mitochondria. J. Biol. Chem.251, 6683–6691
Pande, S.V., Parvin, R. (1980) Carnitine-acylcarnitine translocase-mediated transport of fatty acids into mitochondria: its involvement in the control of fatty acid oxidation in liver. In: Carnitine biosynthesis, metabolism and functions, pp. 143–155, Frenkel, R.A., McGarry, J.D., eds. Academic Press, New York
Panter, R.A., Mudd, J.B. (1969) Carnitine levels in some higher plants. FEBS Lett5, 169–170
Panter, R.A., Mudd, J.B. (1973) Some aspects of carnitine metabolism in avocado. Biochem. J.134, 655–658
Thomas, D.R., Ariffin, A., Noh Hj Jalil, M., Young, B.C.S., Cooke, R.J., Wood, C. (1981) Effect of carnitine on greening barley leaves. Phytochemistry20, 1241–1244
Thomas, D.R., Noh Hj Jalil, M., Cooke, R.J., Yong, B.C.S., Ariffin, A., McNeil, P.H., Wood, C. (1982) The synthesis of palmitoylcarnitine by etio-chloroplasts of greening barley leaves. Planta154, 60–65
Thomas, D.R., McNeil, P.H. (1976) The effect of carnitine on the oxidation of saturated fatty acids by pea cotyledon mitochondria. Planta132, 61–63
Tubbs, P.K., Ramsay, R.R., Edwards, M.B. (1980) Inhibitors of carnitine transport and metabolism. In: Carnitine biosynthesis, metabolism and functions, pp. 207–218, Frenkel, R.A., McGarry, J.D., eds. Academic Press, New York
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Thomas, D.R., Wood, C. Oxidation of acetate, acetyl CoA and acetylcarnitine by pea mitochondria. Planta 154, 145–149 (1982). https://doi.org/10.1007/BF00387908
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DOI: https://doi.org/10.1007/BF00387908