Figure 2.

3D reconstruction of bovine PDC (A and B) and diagrammatic representation of the structural domains of E₂ subunit (C). Shaded-surface representation of 3-fold axes of symmetry of the 3D reconstruction of the bovine kidney PDC (A) and with the closest half removed to reveal the linker (blue) that binds E₁ (yellow) to the E₂ core (green; B). The inner linker is ≈50 Å in length. (C) The C-terminal self-association domain is responsible for the assembly of the dodecahedral scaffold to which E₁ and BP⋅E₃ bind. The N-terminal half of the E₂ comprises the L₁ and L₂ lipoyl domains, and the E₁-binding domain, and their associated linkers. The inner linker is revealed in the 3D structure of the PDC.