Proposed mechanism of Fe-S cluster biogenesis for the SufBCD complex. Biogenesis cycle starts (at left) in the resting state in which SufC is ready for ATP binding. Upon binding of ATP, SufC forms a head to tail dimer. Consequently, the Fe-S cluster binding site between the SufB and SufD interface is exposed to the surface. Nascent Fe-S cluster is built/transferred and ATP is hydrolyzed, restoring the SufBCD complex to its resting state. Hirabayashi K, Yuda E, Tanaka N, Katayama S, Iwasaki K, Matsumoto T, Kurisu G, Outten FW, Fukuyama K, Takahashi Y, Wada K. Functional Dynamics Revealed by the Structure of the SufBCD Complex, a Novel ATP-binding Cassette (ABC) Protein That Serves as a Scaffold for Iron-Sulfur Cluster Biogenesis. J Biol Chem. 2015 290(50):29717-31. PMID: 26472926