Paris/Results
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=== Co-culture experiments === | === Co-culture experiments === | ||
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| + | We want to know if the soma of our synthetic organism will be able to feed the germ line. Unfortunatly, this cannot properly be done without the final construct. Nevertheless, we can already check if in similar situations, dapA deleted strain can survive. | ||
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| + | Two different co-culture experiments were performed: | ||
| + | * In the first one, the dapA deleted strain is grown with a prototroph strain. In this case, we know for sure that the prototroph cells will take the population over. Nervertheless it is interesting to see if dapA deleted strain survive longer in this condition than if alone and without DAP. | ||
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| + | * In the second one, the dapA deleted strain is grown with a strain bearing an auxotrophy to another metabolite. This experiment reproduces cross-feeding works done on the yeast by (look for the exact reference). In this coculture there is a mutual dependence of each strain for the other. If this works for the dapA deleted strain with an other one, then we know for sure that dapA deleted strain can be rescued by a strain producing DAP | ||
=== Recombinaison frequency measurments === | === Recombinaison frequency measurments === | ||
Revision as of 16:26, 18 October 2007
Contents |
Experimental results
Survival of dapA deletant
If we want our system to be robust, the germ line cells should be able to live as long as possible when deprived of DAP. They may indeed face such a feat within our system if their is not enough somatic cells at a given time.
Our dapA deletant strain was grown over night in LB + 300µM DAP. A culture was then launched diluting 100 time the ON culture in LB (+ Kanamycin). 100µL were plated each hour and the number of clone determined.
dapA deletant growth
We expect the somatic cells to excrete only a limited amount of DAP, it would thus be nice if our auxotroph strain could grow on limited amount of metabolite. Over night culture were diluted 100 time in LB suplemented with different amount of DAP.
DAP excretion by prototroph cells
We want to know if prototroph cells are excreting DAP and in what amount. Instead of doing proper chemical dosages which are expensive, we had the idea to make a biological measurments.
Prototroph MG1655 strain was grown in LB, and the medium was recovered at different stages of the culture and purified. The dapA deletant strain was then grown in the recovered medium. The idea is that comparing the growth curve of this experiment with growth curves of dapA deletant in differently supplemented LB medium, should alow us to determine approimatively the amount of DAP present in the recovered medium.
Co-culture experiments
We want to know if the soma of our synthetic organism will be able to feed the germ line. Unfortunatly, this cannot properly be done without the final construct. Nevertheless, we can already check if in similar situations, dapA deleted strain can survive.
Two different co-culture experiments were performed:
- In the first one, the dapA deleted strain is grown with a prototroph strain. In this case, we know for sure that the prototroph cells will take the population over. Nervertheless it is interesting to see if dapA deleted strain survive longer in this condition than if alone and without DAP.
- In the second one, the dapA deleted strain is grown with a strain bearing an auxotrophy to another metabolite. This experiment reproduces cross-feeding works done on the yeast by (look for the exact reference). In this coculture there is a mutual dependence of each strain for the other. If this works for the dapA deleted strain with an other one, then we know for sure that dapA deleted strain can be rescued by a strain producing DAP
