Team:Tuebingen/Measurement
Introduction
After last year’s astonishing Interlab Study results, teams were again asked to take part in the biggest collaboration in the iGEM competition. All teams were asked to characterize the fluorescence for three different GFP devices in relation to each other. This enables an assessment of the devices robustness during use in different laboratories.
Using the gBlocks provided for the study, we built the constructs and transformed them into E. coli DH10beta. The cells were cultured overnight in LB medium containing chloramphenicol as described in the Protocols . Correct cloning was ensured by plasmid miniprep and test restriction. GFP fluorescence was measured in a TECAN plate reader with 488nm excitation wavelength and 520nm emission. We measured three biological replicates with three technical replicates each.
The three promotors are characterised by the iGEM-Team Berkeley in 2006 resulting in the following relative strengths:
- J23101 1791 (Device 1)
- J23106 1185 (Device 2)
- J23117 162 (Device 3)
It was therefore expected, that the construct in Device 1 would produce the highest fluorescence, followed by Device 2 and with a strongly lower fluorescence, Device 3.
Results
We tested the fluorescence intensity produced by three combinations of a varying promoter coupled to the GFP gene.
Our results show, that Device 1 yields a higher fluorescence than the positive control, while Devices 2 and 3 present far lower fluorescence levels. The fluorescence of Device 3 is higher than that of Device 2, which is surprising as the promoter in device 2 was shown previously to have a much higher expression level.
