From 2007.igem.org

Results

Gene Splitting

We were able to split two genes: GFP and RFP. Split GFP has strong green fluorescence. Split RFP's red color is much reduced compared to wild-type RFP. It takes overnight incubation at room temperature for the red color to be visible in white light. Both colors are fluorescent under UV light, although the green color predominates. In the first image below, a negative-control (on the left) does not fluoresce, but split GFP (on the right) does.

The negative control on the left does (hixC-GFP2) not fluoresce, but the experimental split GFP (Plac-RBS-GFP1-hixC-GFP2) on the right does.

We also wanted to test fluorescence phenotypes with both proteins in the same cells. Below on the left are cells containing both split GFP and split RFP, downstream of the T7 RNA polymerase promoter and co-transformed with T7 RNA polymerase plasmid. These cells look bright green, but the red color is hard to see under UV light. Under white light, the green color is not apparent, but the cells are a little pink. The cells only containing split RFP, on the right, are clearly pink under UV light. However, not all cells are equally colored - some are greener than others, which is a curious result as the cells do not contain GFP of any form.

On the left, cells with the T7 RNA polymerase plasmid and a plasmid containing both split RFP and split GFP. These cells fluoresce a bright green under UV light and look pink under white light. On the right, cells with only the T7 RNA polymerase and split RFP.

Cells with only the T7 RNA polymerase plasmid, shown under UV light. There is no fluorescence.

Cells with both the T7 RNA polymerase plasmid and the flipped Hamiltonian Path Problem plasmid, shown under UV light. There is visible green fluorescence.