Rationale: After a successful plaque assay with plaques and a successful picking of a plaque, the purpose of this lab is to perform a plaque assay for purification of the plaques.

Description of Procedures:

The workstation was cleaned using aseptic technique to begin the lab and an ethanol burner was lit to create an aseptic zone. 10 ul of phage buffer was added to 0.5 ml of arthrobacter and allowed to sit for 10 minutes. While sitting, the top agar solution was created for two plates. 4 ml of LB broth and 45 ul of CaCl2 were added to a tube. 5 ml of 2x TA was added to the top agar solution after the 10 minutes were through. 4.5 ml of the top agar solution were added to the arthrobacter and then poured onto a plate labeled LIP 10-3-18 PA-1P. The rest of the top agar solution was poured onto a plate labeled Control 10-3-18 LIP. The plates were allowed to sit for 15 minutes and then inverted and stored in the incubator until the next lab. The workstation was then cleaned using aseptic technique and all materials were properly stored or disposed of.

Observations:

• The plate made with too much phage buffer had two small plaques.
• The control plate had small bubbles in the center.

Interpretations/Next Steps:

The procedure was completed correctly and the lab went smoothly. The next step will to complete a second plaque assay for purification. This will be done approximately two more times.