Title: Plaque Assay for Original Plaque

Date: 24 September 2018

Rationale: The previous 10^0 plaque assays failed, so 2 more plaque assays of 10^0 will be done to determine a phage presence that must pas to continue passaging. Otherwise, soil must be collected again.

Procedure: An aseptic zone was created by washing the lab bench with CiDecon, Ethanol, and lighting a lamp.

– The original plaque assay (9/19/18) was picked to create a new 10^0 lysate for plating. This test will determine if the soil is still viable for passaging. After the new 10^0 was picked, the following recipe was used to make 9 plaque assays (8 PA, 1 Top Agar Control):

• 18 mL LB Broth
• 22.5 mL 2x TA
• 202.5 microliters CaCl2

~ 4.5 mL pipetted into vial containing 0.5 mL Arthrobacter + 10 microliters 10^0 lysate. The vial was then plated, cooled for 10-15 min, and incubated. A Top Agar control was also plated and incubated

Conclusions: If the 2 plaque assays do not grow, soil will be collected again to re-passage a collected phage. If the plates pass, the dilution and passaging process will resume for the present phage to eventually isolate.