Tecnai tf20

Aliquots (either neat, diluted or redispersed in ethanol) of the solid samples were deposited onto holey carbon TEM grids (Agar Scientific), which were transferred into a special anaerobic transfer holder (Gatan 648 Double tilt). This allowed the safe anaerobic transfer of the highly reactive samples to the TEM instrumentation. All samples were freshly synthesized just immediately prior to TEM analyses. The effect of the dilution with ethanol was tested and compared to a nonethanol diluted sample and no changes were observed in the resulting images or spectral and diffraction information.
HR-TEM imaging, selected area electron diffraction and energy dispersive X-ray (EDX) spot analysis were acquired using a Field-Emission-Gun-Transmission-Electron microscope (FEI Tecnai TF20) fitted with a CCD Camera (Gatan Orius SC600A) and an EDX spectrometer (Oxford Instruments 80 mm² X-max). The microscope was operated at 200 kV. To avoid beam damage, the exposure for image collection was limited to maximum 0.25 s. Images were analyzed using the ImageJ software^{37 (link)}. Atomic plane distances were calculated from the fast FFT analyses of several particles from the each acquired high-resolution image and from different areas in each image. The lattice planar distances were then calculated from the reciprocal values of the distance from the spots to the center (Supplementary Table 3).

Ten milliliters of filtered P. multocida Pm172 phage lysate were centrifuged at 40,000 × g for 90 min at 4 °C. The supernatant was carefully removed and the pellet was re-suspended gently with 0.5 ml of 0.1 M ammonium acetate (pH 7.3). The suspension was stored overnight at 4 °C for negative staining and visualization by TEM. Three hundred-mesh carbon-coated nickel grids were dropped onto 50–100 µL of phage suspension. The grids were allowed to adsorb phage suspension for 2 min. The grids were washed 3 times with dH₂O for 10″, excess fluid was removed using Whatman filter paper and the grids were negatively stained with 2% ammonium molybdate for 30″. Excess staining solution was removed with Whatman filter paper. The grids were allowed to dry at room temperature for ~15–20 min. The samples were examined by TEM (FEI Tecnai TF20) at 200 kV using Gatan Microscopy Suite Software.