Abstract
When T. pyriformis is grown in the presence of 10(-2)M-mevalonic acid, the uptake exceeds the cell's requirement for this biosynthetic intermediate. The majority of the excess mevalonic acid is diverted into ubiquinone-8 biosynthesis whereas the biosynthesis of tetrahymanol, the major product of the mevalonic acid pathway, is unchanged. In the presence of excess external mevalonic acid, the biosynthesis of mevalonic acid by the cell is inhibited. It is proposed that ubiquinone biosynthesis is normally regulated by mevalonic acid availability, whereas tetrahymanol biosynthesis is regulated primarily at a later point in the pathway.
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Selected References
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- Beedle A. S., Munday K. A., Wilton D. C. Studies on the biosynthesis of tetrahymanol in Tetrahymena pyriformis. The mechanism of inhibition by cholesterol. Biochem J. 1974 Jul;142(1):57–64. doi: 10.1042/bj1420057. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Brown M. S., Goldstein J. L. Multivalent feedback regulation of HMG CoA reductase, a control mechanism coordinating isoprenoid synthesis and cell growth. J Lipid Res. 1980 Jul;21(5):505–517. [PubMed] [Google Scholar]
- Faust J. R., Goldstein J. L., Brown M. S. Synthesis of ubiquinone and cholesterol in human fibroblasts: regulation of a branched pathway. Arch Biochem Biophys. 1979 Jan;192(1):86–99. doi: 10.1016/0003-9861(79)90074-2. [DOI] [PubMed] [Google Scholar]
- VAKIRTZI-LEMONIAS C., KIDDER G. W., DEWEY V. C. UBIQUINONE IN FOUR GENERA OF PROTOZOA. Comp Biochem Physiol. 1963 Apr;9:331–334. doi: 10.1016/0010-406x(63)90168-3. [DOI] [PubMed] [Google Scholar]
- Warburg C. F., Wakeel M., Wilton D. C. The role of squalene synthetase in the inhibition of tetrahymanol biosynthesis by cholesterol in Tetrahymena pyriformis. Lipids. 1982 Mar;17(3):230–234. doi: 10.1007/BF02535109. [DOI] [PubMed] [Google Scholar]
- Wilton D. C. The effect of cholesterol on ubiquinone and tetrahymanol biosynthesis in Tetrahymena pyriformis. Biochem J. 1983 Oct 15;216(1):203–206. doi: 10.1042/bj2160203. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Zander J. M., Greig J. B., Caspi E. Tetrahymanol biosynthesis. Studies in vitro on squalene cyclization. J Biol Chem. 1970 Mar 25;245(6):1247–1254. [PubMed] [Google Scholar]