Catalase and Hydrogen Peroxide Exposure

     After reviewing the original paper our project was based on at the end of last week, we decided to try and edit our hydrogen peroxide exposure protocols in order to get a better result. This mostly meant adding catalase at the end of our incubation period, along with some other minor changes. 


    We started the week of with some inoculations and graham stains, and spent a good amount of time preparing for a biotech program booth that we would be setting up later that day. 


    Wednesday we finally got to the new hydrogen peroxide exposure. We started by diluting down 11.5M H2O2 down to 200mM. We also diluted down our six groups of cells all down to an OD close to 1. 

After pelleting all of our cells, we removed the supernatant, and resuspended all of the cells in 200μl of PBS. 

We than re-pelleted, and added 200μl of H2O2 to our test cells, and 200μl of PBS to our control cells.

Next we incubated the cells for 30 minutes at 30°C.

After we immediately added 100μl of catalase to stop the H2O2, and let sit for two minutes.

We than pelleted the cells, removed the supernatant, and washed the tubes with 400μl of PBS twice. 

After spinning once more to remove all supernatant, we froze the pellets at -80°C.



    We ended the week with pouring about 20 plates, in preparation for the next few weeks. Aside from the Hydrogen peroxide exposure, not much was done this week. 

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