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Figure 3
The CTBGPGPMPR structure reveals the expected pentameric ring arrangement typical of wild-type CTB but not the structure of the MPR. Cartoon representation of the crystal structure of CTBGPGPMPR in two orientations: (a) top view, (b) side view. Each subunit is indicated by a different color. The C-terminus of one of the subunits is indicated in red. This region is shown in close-up in (c). (c) 2FoFc electron-density map at a contour level of 1.5σ of the C-terminus of CTB in CTBGPGPMPR, which was phased with the pentameric CTB model (PDB entry 1jr0 ; Pickens et al., 2002BB62) using molecular replacement (McCoy et al., 2007BB35). Electron density can be seen beyond the terminal asparagine of CTB where the GPGP linker and MPR connect.

Volume 1| Part 5| August 2014| Pages 305-317
ISSN: 2052-2525