Selected representation of 2D class averages from the large particles used for 3D reconstruction, indexed 110. The number of particles that were included in each average are indicated at the top of each class in green. Classes 14, 6, and 8 are face views, and classes 5, 7, 9, and 10 are side views. Note that while class 8 shows 10 protomers, the other face views have 9 protomers, which are more abundant. Asymmetry is observed in classes 2 and 4 where one of the peripheral spikes assumes a different conformation than the other eight. There are two types of side view presentations: classes 5 and 7 with a wide, arced perspective of the upper density (TIR domains array) and classes 9 and 10 with a narrow, tilted view of that density.
