Low iron concentration and aconitase deficiency in a yeast frataxin homologue deficient strain.

Deletion of the yeast frataxin homologue, YFH1, elicits accumulation of iron in mitochondria and mitochondrial defects. We report here that in the presence of an iron chelator in the culture medium, the concentration of iron in mitochondria is the same in wild-type and YFH1 deletant strains. Under these conditions, the activity of the respiratory complexes is restored. However, the activity of the mitochondrial aconitase, a 4Fe-4S cluster-containing protein, remains low. The frataxin family bears homology to a bacterial protein family which confers resistance to tellurium, a metal closely related to sulfur. Yfh1p might control the synthesis of iron-sulfur clusters in mitochondria.