Number of Fluoride Ions Binding to Succinate Dehydrogenase during Mixed Inhibition
نویسندگان
چکیده
We have measured the number of fluoride ions bound to one molecule of succinate dehydrogenase (SDH) of submitochondrial particles from porcine kidney cortex. Enzyme activity was studied according to the method of Dixon and the number of fluoride ions bound was established arithmetically. A mixed competitive and noncompetitive inhibition of SDH by fluoride was confirmed. At high levels of succinate (~20 mM) that saturate the active site of the enzyme, the binding of one fluoride ion outside the site results in noncompetitive inhibition. At lower levels (~1 mM), the site is not saturated and inhibition is competitive, with two fluoride ions binding to each enzyme molecule.
منابع مشابه
The effect of silver ions on the respiratory chain of Escherichia coli.
BKAGG, P. D., and D. J. RAINNIE. 1974. The effect of silver ions on the respiratory chain of Esclrerichia coli. Can. J. Microbiol. 20: 883-889. Silver ions inhibited the oxidation of glucose, glycerol, fumarate, succinate, Dand L-lactate, and endogenous substrates by intact cell suspensions of Esclrerichia coli. Silver ions reacted with the respiratory chain at two levels. The site nlost sensit...
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