Fig. 2.

The composition of Msm Sdh1 and comparison with types A–D complex IIs. (A) SdhA, SdhB, and SdhC with prosthetic groups are presented in cartoon mode. FAD and FeS clusters are shown as spheres. (B) Structural superimposition of Msm Sdh1 with Msm Sdh2 (type A, PDB code 6LUM), W. succinogenes QFR (type B, PDB code 1E7P), Sus scrofa SQR, (type C, PDB code 1ZOY), and E. coli QFR (type D, PDB code 1L0V). Corresponding cartoon models and rotation angles are shown. Msm Sdh1, Sdh2, and W. succinogenes QFR, S. scrofa SQR, and E. coli QFR are in magenta, light-blue, pale cyan, orange, and gray, respectively.