Rationale

Today we will wash and enrich soil sample C for the second time. This soil was previously tested and yielded positive results for one member of the lab group, and negative results for the other two members of the group. Due to the inconsistency, the soil sample C will be tested again.

Procedure

• 2 mL of soil and 10 mL of LB broth were added to a vial. The vial was vortexed for 10 minutes and then centrifuged at 5000g for 10 minutes.
• The supernatant produced was then dispensed into another vial and 0.5 mL of Arthrobacter was added.
• The vial was placed into the incubator where it was shaken for 48 hours.

Observations

Due to the lack of filters, the supernatant was directly poured out of the vial and into another. This allowed for debris to be transferred and the resulting enriched isolation to be cloudy rather than clear.

Conclusion/Next Steps

Next, we will test soil sample C again through PCR and gel electrophoresis in hopes of phage presence.