Metabolism of fluoroacetate
produces an inhibitor of the citric acid cycle enzyme, aconitase.
Fluoroacetate is known as a suicide substrate because by
itself it is not toxic to cells, but it kills cells by being made
into a toxic substance. For fluoroacetate, this occurs
as follows:
Cells readily convert fluoroacetate to fluoroacetyl-CoA in a reaction catalyzed by the enzyme acetate thiokinase (reaction diagram). Fluoroacetyl-CoA can combine with oxaloacetate to form fluorocitrate in a reaction catalyzed by the citric acid cycle enzyme, citrate synthase. Fluorocitrate is toxic to cells because it inhibits aconitase.
Fluoroacetate is a plant product that has been used as a pesticide. Its use by ranchers in the West to control coyote populations has led also to the death of eagles.