Figure 2
Structure and cohesin-dockerin interface of RfCohScaB3-Doc1a and RfCohScaA-Doc1b. (A) Structure of RfCohScaB3-Doc1a complex with the dockerin in green and the cohesin in light blue. The dockerin N- and C- terminus and the α-helices are labeled, and a dotted molecular surface representation is shown. The cohesin blue molecular surface is represented. (B) Structure of RfCohScaA-Doc1b complex with the dockerin in gray and the cohesin in brown, using a similar layout as in panel A. but showing instead the transparent gray molecular surface of the dockerin. (C) Overlay of both complexes showing the main polar interactions at the Coh-Doc interface. (D) Overlay of both complexes showing the main hydrophobic interactions at the Coh-Doc interface. In panels C and D. the most important residues involved in Coh-Doc recognition are depicted as ball&stick configuration, with a dark background label for the Doc residues and a light background label for the Coh residues, using the Doc1a/Doc1b and CohScaB3/CohScaA numbering. Solid black lines mark hydrogen-bonds interactions. Ca2+ ions are depicted as purple spheres. In all panels, the transparent orange disk marks the plane defined by the 8-3-6-5 β-sheet, where the β-strands form a distinctive dockerin-interacting plateau.
