Figure 4.

Helical arrays of a macromolecular complex and two proteins formed on charged lipid tubules. (A) Helical array of RNA polymerase on a DO-Ethyl-PC functionalized lipid tubule (positive surface charge), negatively stained with 1% uranyl acetate. The diffraction pattern below shows visible peaks to 1/38 Å⁻¹ (arrowhead). (Magnification ×140,000.) (B) Cryo-electron micrograph of a helical array of g-actin on DO-Ethyl-PC functionalized lipid tubule (positive surface charge). The diffraction pattern below shows visible peaks up to 1/35 Å⁻¹ (arrowhead). (Magnification ×152,000.) (C) Helical array of annexin V on DOPS functionalized lipid tubule (negative surface charge) negatively stained with 1% uranyl acetate. The diffraction pattern below shows visible peaks up to 1/40 Å⁻¹ (arrowhead). (Magnification ×152,000.)