Purification and properties of carnitine acetyltransferase from citric acid producingAspergillus niger
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Carnitine acetyltransferase was purified from the citric acid producingA. niger mycelium with a protein band showing a relative molecular weight of 77,000 and a pH optimum of 7.3. TheK m values for the purified enzyme for acetyl-CoA and for carnitine were 0.1 mM and 1 mM, respectively. Carnitine acetyltransferase was located both in the mitochondria and in the cytosol. Both mitochondrial and cytosolic enzyme were purified using ammonium sulfate precipitation, Mono Q and Superose 12 separation. Regarding the localization, except for maximum velocity, there were no differences observed in substrate specificity and inhibition. Inhibition of the enzyme with micromolar concentrations of Cu2+ could contribute to a greater citric acid biosynthesis. Carnitine acetyltransferase can be considered as an enzyme necessary for the transport of acetyl groups through mitochondrial membrane in both directions.
Index entriesCarnitine acetyltransferase citric acid Aspergillus niger enzyme kinetics inhibition
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- 5.Kozulic, B., Mosbach, K., and Meussdoerffer, F. (1988),Biochem. J. 253, 845–849.Google Scholar
- 11.Kohlhaw, G. B. and Tan-Wilson, A. (1977),J. Bacteriol. 129, 1159–1161.Google Scholar
- 12.Watson, K. and Smith, J. E. (1968),J. Bacteriol. 96, 1546–1550.Google Scholar
- 16.Kispal, G., Cseko, J., Alkonyi, I., and Sandor, A. (1991),Biochem. Biophys. Acta 1085, 217–222.Google Scholar
- 19.Mijazawa, S., Ozasa, H., Furuta, S., Osumi, T., and Hashimoto, T. (1983),J. Biochem. 93, 439–451.Google Scholar