Week 7: Contamination Issue and New Plan

 

Introduction: 

    Unfortunately this week, Jessica, Kaylee, and I found an unusual growth curve in our 96 wells plate that we figured could be a sign of contamination. To go into deeper details, our negative control had only TGY but it showed an unusual growth curve that we might've guessed that there was a type of bacteria in our TGY and that it is contaminated. 

Discussion: 

Fig. 1 









As shown in the results and our negative control, from the H wells, it only contains TGY but it showed a growth curve. 

Fig. 2 










Knowing this information, we decided to do a gram stain to see what type of bacteria contaminated the TGY. Dr. Tuohy suggested that the gram stain was gram negative and could perhaps been caused from a pipetting error since we have pipetted many times in the wells. Since this procedure failed, we will conducting a new plan and make new media. 

Fig. 3 


After talking and taking some advice from Jonathan, we decided to change up our wells set up a bit. Our A-D and 1-6 wells will likely stay the same with the same measurements of TGY, kanamycin, and the bacteria; aquaticus. However, instead of having only TGY in our negative control (H wells), we will be adding kanamycin due to the fact that it is also a constant control. 


Comments

  1. EricaNovember 4, 2022 at 9:09 AM

    Don't forget to cite your sources, better luck next week!

    ReplyDelete

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