Week of 9/23/24-9/27/24

Intro

Once again, the week was dedicated to desiccation and RNA extraction procedures. Notably, there were interesting results from some of the gram stains, and it was decided to make new freezebacks because of this. 

Methods

Samples A, B, & C were OD'ed and normalized to a value of 1.0 (+/- .1), then cells were packed by centrifuging, washing, then adding 1mL of OD'ed sample from a separate eppendorf tube. Samples were plated onto kapton squares in a 6 well plate, with spots containing 100uL of sample each. Samples were also placed into *new* desiccator to sit over the weekend for a total of 2 days of drying time and 2 days in the desiccator.

Results & Discussion

Cells that were gram stained this week looked like this:

The gram negative color is characteristic of D. deserti, but the cells are usually rod-shaped. All of the gram stains done showed the same gram negative color but cocci shape. Despite this, it was decided to move forward because occasionally cells that have been passaged many times, or been in the freezer (freezebacks), the cells can undergo morphological changes. As all of the samples shared this shortening, it was decided that this must be some sort of morphological change and to proceed as normal.

Conclusion

Due to time constraints, we decided not to finish the RNA extraction of the control samples and to simply hold off until next week. The samples were OD'ed and normalized then placed in the -80°C. The next week, we will conduct the RNA extraction on the control samples as well as the samples that were placed in the desiccator for 48 hours.

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