Fig. 4. Constructing the tripartite PQM complex.
a Left: AlphaFold model of the tripartite complex between HiSiaQM and HiSiaP in the Ci state. Right: The outward open model of HiSiaQM (Co state, Fig. 2d). Here, the P-domain was replaced by the open (substrate-free) structure of HiSiaP (2CEY) by aligning it onto the N-terminal lobe of the P-domain in the Ci state (left). b “Open book” view of the interface regions between QM and the N- (III) and C-lobe (IV) of the P-domain. The color code corresponds to the conservation of residues, calculated by Consurf85. The highlighted residues are in regions I–V that are likely important for complex formation and were analyzed in the growth assay in Fig. 5.