Figure 4.

AlphaFold3 models for the various SufBC₂D complexes. Amino acid sequences for each protein were submitted to the AlphaFold3 webserver. The highest ranking models for SufBC₂D (0.77 ipTM, 0.8 pTM), SufBC₂D–E (0.78 ipTM, 0.79 pTM), and SufBC₂D–E-2MgATP (0.76 ipTM, 0.79 pTM) are shown. Models are colored by subunit with key cysteine residues shown as spheres with the thiol sulfur in yellow. SufB residues 79–157 are highlighted in magenta as these residues are not visible in the 5awf structure. The red arrows indicate the distance between C51 SufE and C254 SufB where persulfide transfer takes place. Mg-ATP is shown in yellow within SufC protomers. Models colored by AlphaFold3 confidence score and predicted alignment error plots are shown in Fig. S3.