Fluoroacetate succinate

Krebs cycle Inhibition of aconitase by superoxide and fluoroacetate, of succinate dehydrogenase by methamphetamine and mal-onate, of alpha-ketoglutarate dehydrogenase by salicylic add... 

There are two Krebs cycle inhibitors that are worth mentioning. Malonate inhibits succinate dehydrogenase because of its very similar structure. Fluoro-acetate inhibits cis-aconitase, which is an Fe-S enzyme. The fluoroacetate replaces acetate as a substrate in the citrate synthase reaction when this combines with cis-aconitase, however, no further reaction becomes possible. 

Collicchio-Zuanaze, R.C., Sakate, M., Schwartz, D.S., Trezza, E., Crocci, A.J. (2006). Calcium gluconate and sodium succinate for therapy of sodium fluoroacetate experimental intoxication in cats clinical and electrocardiographic evaluation. Hum. Exp. Toxicol. 25 175-82. 

Oxalic acid (jplanttoxln) and fluoroacetate (rodentidde), which inhibit succinic dehydrogenase and aconitase, respectively, in the tricaiixixylic add (TCA) cyde... 

This normally requires the functioning ot a series of enzyme systems within the cell. The formation of succinyl CoA requires a citric acid cycle as shown by Shemin s tracer studies with succinate-1,4-C and succinate-2,3-C this was also shown by inhibition studies with malonate, trans-aconitate, fluoroacetate, or arsenite (35). Coupled to the citric acid cycle is an electron transfer system to O as shown by inhibition by CO and anaerobiosis. Inhibition by dinitrophenol su ests that oxidative phosphorylation is required, although dinitrophenol may inhibit 5-AL synthetase more directly (36). For AL synthesis, pyridoxal-P is required as shown by Schulman and Richert (37) on vitamin B -dehcient chicks and by inhibitors of pyridoxal-P, e.g., deoxypyridoxine, isonicotinic hydrazide, etc. (35). 

Figure 9 F H -NMR spectra of fluoroacetate (-220 ppm) and 4-fluorothreonine (-234 ppm) after 48h incubation of [ H4]-succinate with a S. cattleya cell suspension.

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