Correlated cryogenic photoactivated localization microscopy and cryo-electron tomography - PubMed (original) (raw)

Figure 2

New T6SS structures identified by correlated cryo-PALM-ECT. (a) A very short loaded T6SS structure with baseplate attached to membrane. Superposed low-resolution EM image, cryo-PALM signal, high-resolution cryotomographic slice, and object segmentations as in Figure 1. (b) Tomographic slice through the tubular structure corresponding to the segmentation model shown in a. Features of the T6SS highlighted in blue (sheath) and cyan (baseplate). (c) Tomographic slice in b without highlights. (d) Cross-section view of the T6SS sheath in c. (e) A bent T6SS structure with additional sheet, distinguished from other tubular structures in the vicinity. Segmentation of the cryotomogram shows different tubular structures (individually colored blue, pink, and green) and spherical granules (white). Scale bar in e 400 nm (applies to a, e). (f, j, m) Segmented models of tubular structures shown in e. (g, k, n) Tomographic slices through the tubular structures corresponding to the segmentation models shown in f, j, and m, respectively. White arrows in g indicate a sheet adjacent to the hollow tube. (h, i) Tomographic slices of cross-sections h' and i' of the tubular structure shown in g. (l, o) Cross-sectional views of k and n, respectively. Diameters of the tubules shown in d, h, l, and o are 13, 14, 20, and 33 nm, respectively. Scale bar in o 50 nm (applies to b, c, d, g, h, i, k, l, n, o).