Low-magnification were taken at 5600x (object pixel size 2.18 nm) to generate lamella overviews. High-magnification (18,000x, 27,500x, 34,000x, 42,000x) with a pixel size of 0.65, 0.42, 0.34, 0.32 nm respectively) tilt series were recorded at sites of interest using the SerialEM software (Mastronarde, 2005), operating in low dose mode with tracking and focus enabled.