Rationale

Today we will collect soil sample E and metadata on the sample as well.

Procedure

• Established an aspectic zone.
• New soil was collected and 2 mL of it was placed into a vial along with 10 mL of LB broth. The vial was shaken for 10 minutes and then was centrifuged at 5000g for 10 minutes.
• After being centrifuged, the supernatant produced was syringe filtered into another vial and 0.5 mL of Arthrobacter was added. The enriched isolation was placed into the incubator for 48 hours.
• To determine the percent water of the soil, the weigh boat was massed, ~3g of soil was added, and then the weigh boat containing the soil was massed again. It was set under the fume hood for 48 hours to dry.
•  To determine the percent sand/silt/and clay of the soil, 10 mL of soil was placed into a falcon tube and DI water was added to the 30 mL line. 3 drops of soil dispersion liquid were added and the tube was shaken for 45 seconds. The tube was then placed under the fume hood for 48 hours.
• To determine the pH of the soil, 1 mL of soil was added to a pH vial and the rest of the vial was filled with DI water. The vial was shaken for 30 seconds and then was set aside for 10 minutes. The pH was then measured using pH paper.

Observations

Mass of the weigh boat: 2.326 g

Mass of the weigh boat and soil: 6.048 g

pH of soil: 6

10 mL of enriched isolation was able to be produced.

The plaque assay produced from 10/8/18 resulted in contamination and the presence of colored bacteria. Despite the contamination, it was concluded that soil sample D did not have phage presence, therefore another soil sample was collected.

Conclusions and Next Steps

We will conduct a plaque assay with our enriched isolation to test for phage presence. The results of the metadata experiments will be observed as well.