Figure 2.

Native PAGE to visualize the recombination reaction. Approximately 150 ng (20 nM in 30 μl) of the 368 bp educt was incubated with 4 μM FLP in FLP buffer either without BSA or supplemented with 100 μg/ml BSA. After reaction samples were proteinase K digested, purified, analyzed on 8% PAGE and scanned for fluorescence of Cy5 and Rhodamine green. While the negative controls without FLP (2 lanes on the right-hand side) only showed the double-labeled educt (yellow color), in the FLP-containing reactions (2 lanes of the left-hand side) two new bands appeared corresponding to the expected recombination products: 314 bp circle (green) and 54 bp linear fragment (red). Owing to its topological state, the band of the circular green-labeled DNA runs above the 368 bp linear band.