Bacteriophage typing method

1. inoculate surface of agar medium with bacterial culture 2. mark 15-20 squares on the back side of the agar plate 3. inoculate agar surface in each square with a drop of phage suspension (using different phage for each square) 4. incubate inoculated agar plates at an appropriate temperature for 24 hours 5. observe plates for plaques (clear zones from cell lysis) 6. record phage type information