FIG. 2.

Superpositions of StScsC and structural homologues. α-carbon trace stereo views of StScsC (black) superposed with (A) StDsbA (cyan), (B) BsBdbD (blue), and (C) the TRX domain of EcDsbG (orange). α5 indicates the position of the fifth alpha helix in the inserted helical domain of DsbA-like proteins StDsbA and BsBdbD. Structures in the left panel are in the same orientation as those in Fig 1B, and in the right panel, all three structures are rotated clockwise 90° around the vertical axis, highlighting the extended loop between α3 and α4 in BsBdbD (indicated with blue asterisk).