Anamorsin Is a [2Fe-2S] Cluster-Containing Substrate of the Mia40-Dependent Mitochondrial Protein Trapping Machinery.
Banci, L., Bertini, I., Ciofi-Baffoni, S., Boscaro, F., Chatzi, A., Mikolajczyk, M., Tokatlidis, K., Winkelmann, J.(2011) Chem Biol 18: 794-804
- PubMed: 21700214 
- DOI: https://doi.org/10.1016/j.chembiol.2011.03.015
- Primary Citation of Related Structures:  
2LD4 - PubMed Abstract: 
Human anamorsin was implicated in cytosolic iron-sulfur (Fe/S) protein biogenesis. Here, the structural and metal-binding properties of anamorsin and its interaction with Mia40, a well-known oxidoreductase involved in protein trapping in the mitochondrial intermembrane space (IMS), were characterized. We show that (1), anamorsin contains two structurally independent domains connected by an unfolded linker; (2), the C-terminal domain binds a [2Fe-2S] cluster through a previously unknown cysteine binding motif in Fe/S proteins; (3), Mia40 specifically introduces two disulfide bonds in a twin CX(2)C motif of the C-terminal domain; (4), anamorsin and Mia40 interact through an intermolecular disulfide-bonded intermediate; and (5), anamorsin is imported into mitochondria. Hence, anamorsin is the first identified Fe/S protein imported into the IMS, raising the possibility that it plays a role in cytosolic Fe/S cluster biogenesis also once trapped in the IMS.
Organizational Affiliation: 
Magnetic Resonance Center CERM, University of Florence, Via L. Sacconi 6, 50019, Sesto Fiorentino, Florence, Italy. banci@cerm.unifi.it