| Autor: |
Pedersen, B. N., Gromek, A., Daehnfeldt, J. L. |
| Zdroj: |
Experimental Biology and Medicine; November 1972, Vol. 141 Issue: 2 p506-509, 4p |
| Abstrakt: |
The presence of extramitochondrial CO2/HCO3-dependent fatty acid synthesis in Ehrlich hyperdiploid ascites tumor cells cultivated in vitrowas demonstrated by the stimulatory effect of increasing CO2tensions (0-5% atm) on the 14C-acetate incorporation into hexane extracts of KOH hydrolysates of intact cells.The incorporation of 14C-acetate into fatty acids of particle-free supernatants of Ehrlich ascites tumor cells propagated in vivowas shown to be dependent on NADPH regenerating systems, such as citrate-isocitrate, glucose or glucose-6-phosphate. The last two compounds, however, stimulated the 14C-acetate as well as the 14C-acetyl-CoA incorporation into fatty acids even in the presence of citrate-isocitrate + NADP. Under the same conditions fructose-1,6-diphosphate produced an inhibition of the acetate incorporation.Determinations of the NADPH concentration of particle-free supernatants fortified with different NADPH generating systems showed that only glucose and citrate-isocitrate could stabilize the NADPH level, while fructose-1,6-diphosphate and pyruvate would lower or completely exhaust the NADPH content.The mechanism of the stimulatory effect of glucose on acetate incorporation in particle-free supernatants is discussed. |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
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