Exeter/26 July 2013

From 2013.igem.org

Exeter iGEM 2013 · Paint by Coli

Results from transformation

Part Part Code Number of Colonies
OmpR BBa_K098011 0
OmpR promoter (a.k.a ompC) BBa_R0082 1
FixJ promoter (a.k.a FixL) BBa_K592006 20
RBS + cph8 BBa_K592018 34
YF1 blue light sensor BBa_K592004 10
CcaR BBa_K502002 8
Terminator BBa_B0015 3
lambda inverter system BBa_Q04501 0
Promoter + RBS BBa_K608002 5
RFP control - 60

The OmpR BioBrick and lambda inverter system never transform, but why? We can come up with a reasonable explanation for OmpR; the OmpR protein is already present in E. coli, and is involved with osmotic regulation. Inserting a high-copy number plasmid with the OmpR gene included and creating far more OmpR in the bacteria than is normally present is probably killing the cells. We'd initially assumed, on our first transformation, that we'd plated our bacteria onto the wrong antiobiotic, but this would not have been possible in the subsequent transformations (we've been very cautious ever since!).

However, we are still struggling to explain the failure of the lambda inverter system. We have looked at a multitude of papers, and the cI repressor protein coded for by BBa_Q04510 shouldn't have any effect on the cells, and yet...

Take me back to the notebook.

Exeter iGEM 2013 · Paint by Coli