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Team:Bielefeld-CeBiTec/Notebook/Journal/rMFC/Jun
From 2014.igem.org
June |
 |
- Initial cultivation experiments with neutral red
- This week we wanted to test the properties of neutral red during a cultivation on a small scale
- Cultivation of the E. coli strain with porines (attempt 1) and wildtyp as control (attempt 2) in LB-medium with 100 µM neutral red
- pH was set up at 8.75
- Results
- Attempt 1 turned red (pH = 7.495)
- Attempt 2 remained yellow
- Reduction and oxidation of neutral red
- This week we checked the properties of neutral red under oxidizing and reducing conditions by adding chemical agents
- Reducing agent: sodium dithionite
- Red solution got reduced and turned colorless
- Got oxidised by air again afterwards
- Oxidizing agent: hydrogen peroxide
- Red solution stayed red
- Yellow solution stayed yellow
- Conclusion: the color of the solution depends on the pH
- Further cultivation experiments with neutral red
- This week we cultivated E. coli in LB-medium with 100 µM neutral red which was reduced by different concentrations of sodium dithionite before
- Attempts and controls
- Negative controls:
- 0 µl of sodium dithionite
- 100 µl of sodium dithionite
- 200 µl of sodium dithionite
- 500 µl of sodium dithionite
- Positive control:
- 0 µl sodium dithionite with E. coli
- Attempts:
- 100 µl sodium dithionite with E. coli
- 200 µl sodium dithionite with E. coli
- 500 µl sodium dithionite with E. coli
- Results
- Negative controls: all controls got colored probably through oxidation by air
- Positive control: turned yellow and turbid probably because of alkaline conditions and high cell density
- Attempts: all attempts turned red but no turbidity is visible probably because sodium dithionite could be toxic to the cells
