Figure 4
From: Nano-encapsulated Escherichia coli Divisome Anchor ZipA, and in Complex with FtsZ
TEM of SMALP-ZipA. (a) Negative stain micrograph (2% Uranyl acetate) of SMALP-ZipA after SEC, selection of individual particles are illustrated with white circles, (b) Individual particles from the micrographs are illustrated to show SMALP-ZipA particles. (c) Cryo-EM image of SMALP-ZipA, the edge of the hole in the carbon support film of the EM grid is visible at the top right of the image. The particles highlighted by white circles are 10–16 nm in diameter and are relatively monodispersed. (d) Classification of the particles reveals elongated shape of approximately 6.5 nm in width and 16 nm in length. The box size is 19.52 nm. (e) further refinement of the structure against all the raw particles. Fourier shell correlation (FSC) for the refined structure using the gold standard 0.143 gives a resolution of 1.6 nm. (f) The 3D reconstruction of SMALP-ZipA using EMAN2 is displayed with the X-ray crystal structure of ZipA GD (PDB 1F47 with FtsZ 17aa C-terminal peptide) docked within the area protruding from the nanodisc (blue ribbon) showing very good fit. Orthogonal views are shown, giving a length of 16.nm, and width of 6.5 nm.
