Fig. 4: Structures of PscX and PscY and their interactions with the CabRC core.
From: Structure of the Acidobacteria homodimeric reaction center bound with cytochrome c
a The PscX‒PscY subcomplex interacts with the CabRC core at different sites. Details in the square boxes are presented in (b), (e), and (f). b Arrangement of the PscX‒PscY subcomplex in the CabRC. The interface of the two proteins is indicated by a black ellipse. c Superposition of the monoheme binding domains of PscX and PscY. d Hydrogen bonds (black dotted lines) formed between residues at the interface of PscX and PscY. e, f Magnified views of the interactions between PscX or PscY and the CabRC core in the transmembrane region. The brown and green boxes (in left panels) are enlarged, and the enlargements (center) show the main hydrophobic interactions between PscX or PscY and the CabRC core; the hydrophobicity is colored red. The dark blue and cyan boxes are further enlarged, and the enlargements (right) show the hydrogen bonds are indicated by black dotted lines. g Magnified views of the interactions between PscX or PscY and the CabRC core in the periplasmic region. All salt bridges are indicated by red dotted lines.
