Required for lysine and glutamate prototrophy and mitochondrial genome maintenance. Has a role in the maturation of mitochondrial aconitase-type and radical-SAM Fe/S proteins biotin synthase and lipoic acid synthase. Interacts with CCR4, ISA1 and ISA2. Up-regulated during calcium shortage. Present with 2960 molecules/cell in log phase SD medium. Belongs to the GcvT family. CAF17 subfamily.