Rationale

Today we will conduct a plaque assay and collect soil metadata on the new soil collected.

Procedure

• Established an aseptic zone.
• 10 µL of enriched lysate was micropipetted into a vial containing 0.5 mL of Arthrobacter. It was set aside for 10 minutes.
• 8 mL of LB broth was aliquoted into a tube along with 90 µL of CaCl2 and 2X TA. The solution was mixed by pipetting up and down, and 4.5 mL of the solution was pipetted into each tube containing the 10 µL of enriched lysate and 0.5 mL of Arthrobacter.
• The mixed solution was then poured onto a petri dish and was set aside for 10 minutes.
• The percent water in the soil was observed by massing the weigh boat, which was used to determine the % water in the soil.
• The amount of sand/silt/and clay in the soil was observed by seeing the total amount of soil that was present in our falcon tubes , the amount of sand, the amount of silt, and the amount of clay.
• The area was cleaned.

Observations

Percent water in the soil: ((3.88-3.231)/3.88) x 100= 16.7%

Total amount of soil in the falcon tube: 7 mL

Amount of sand: 5.5 mL

Amount of silt: 1 mL

Amount of clay: 0.5 mL

Percent sand: 78.57%

Percent silt: 14.28%

Percent clay: 7.14%

No air bubbles formed when pouring the top agar into the plate.

Conclusion/Next Steps

We will assess the results of the plaque assay and determine if there is phage presence or not. From there we will conduct a spot test to confirm our results.