Phage Morphology Visualization by Electron Microscopy

Phage morphology was investigated using a FEI Tecnai G2 electron microscope as previously described [25 (link)]. Briefly, a 6 μl aliquot of Amicon-concentrated, CsCl-purified phage lysate was applied to a copper mesh PLECO grid (Ted Pella Inc., Redding, CA), blotted with 90 mm Whatmann® filter paper Grade 597, negative-stained for 10 s with 8 μl 0.75% uranyl acetate (Sigma-Aldrich, Darmstadt, Germany), and blotted again. The grids were dried for 2 h and stored at ambient temperature for viewing within 24 h. Grids were evaluated at magnifications ranging from 38,000–40,000 × for 20 nm scale images, and 20,000 × magnification for 50 nm scale images.