Figure 36.

Metal-mediated protein cage via orthogonal chemical interactions. a) Structural overview of the cyt cb₅₆₂ scaffold. Salient structural elements are shown as sticks. b) C₂-symmetric protein dimerization induced by tetrahedral Zn²⁺ coordination of native amino acid side chains. c) C₃-symmetric protein trimerization induced by octahedral Fe³⁺-tris-hydroxamate coordination. Surface representations of the BMC3 cage (d) and BMC4 cage (e), with metal ions shown as colored spheres. Insets show atomic details of each metal coordination site, with the mF_o − DF_c electron density omit map (blue mesh) contoured at 3σ. Adapted with permission from Ref.¹⁹⁵. Copyright 2020 NPG.