Characterization of phages. Plaques produced by each individual virus (on
nutrient plates) were examined for plaque morphology and measured (in mm).
Individual viruses were then examined by transmission electron microscopy
(TEM). For TEM, a mesh copper grid with carbon-coated Formvar film was
floated on a droplet of the phage sample and then stained with 2% uranyl
acetate. Images (15,500 and 28,500 magnifications) were collected using a
Philips CM-100 TEM operated at 80 kV, spot 3, 200-m condenser aperture, and
50-m objective aperture.