FIGURE 4.

Summary of the quaternary structure deformations observed in the CutR/EutS/PduU subfamily of BMC shell proteins. (a) Geometric representation of adjacent pairs of permuted BMC shell protein subunits from three flat or very nearly flat hexameric structures (CutR Hexamer 1, CutR Hexamer 2, and PduU) after aligning their A subunits (gray). The relative position of the B subunits is shown for CutR Hexamer 1 (lime green), CutR Hexamer 2 (orange), and PduU (forest green). (b) Similar representations for the two screw forms (CutR Screw 1 (magenta) and CutR Screw 2 (purple) relative to the flat CutR form (gray). (c) A similar representation of the bent EutS structure (teal, PDB ID 3I96) relative to the flat CutR form (gray). (d) Overlay of all A monomers relative to the flat hexamer with the B monomers colored as follows: Cut R flat Hexamer 1 (lime green), Cut R flat Hexamer 2 (orange), PduU (forest green), CutR Screw 1 (magenta), CutR Screw 2 (purple), and EutS (teal). The rotation of adjacent subunits in alternate assembly forms, as calculated in Table 1, is diagrammed