Date: Friday, October 12th, 2018

Title: Soil Sample C Washing and Enrichment

Rationale: The purpose of today’s lab was to filter and enrich the soil sample in order to prepare a lysate that can be tested.

Class Question: Is there a difference in bacteriophage presence or type in soil samples taken from live oaks vs those from red oaks?

Procedure:

1. An aseptic zone was set up.
2. Soil Sample C was used to fill a 15 mL conical to the 2 mL mark.
3. LB broth was used to fill the conical to the 13 mL mark.
4. The 15 mL conical was vortexed for 15 minutes.
5. The conical with soil and LB broth was massed and found to be 19.470 g.
6. A second conical with the same weight was made using water in order to spin the conicals for 10 minutes at 10,000 gs.
7. 1 mL of the supernatant was filtered out using a syringe filter with a 22 micrometer filter and placed in another 15 mL conical to be used as the direct isolation.
8. ~10 mL of the supernatant was filtered out using a syringe filter with a 22 micrometer filter and placed into a 50 mL conical.
9. The lysate in the 50 mL conical was mixed with .5 mL arthrobacter and left to incubate over the next 72 hours.

Observations: At some point the 50 mL conical was possibly exposed to contamination when the lid was left open during a conversation. This occurred in an aseptic zone but will be noted and watched for.

Results: This experiment yielded an enriched and direct lysate which can be used for a spot test or plaque assay.

Next Step: The next step is to use a plaque assay or a spot test in order to test for plaques.