Electrophoretic mobility shift assays. The investigated binding sites in front of the genes pdhR, glcD, mraZ, and metB are displayed on the lower line. The left hand panel demonstrates an assay for 0.1 pmol of each DNA fragment without PdhR. For the assay shown on the right hand site, samples were incubated with 54 pmol purified PdhR prior to electrophoresis. Complex formation of regulator protein and DNA fragment leads to a shifted DNA-signal, which is assigned by the grey box. A strong PdhR-DNA complex is detected for the binding site in front of the pdhR gene for the known self-regulation. The same binding activity was monitored for the glcD binding site. Very weak affinity of PdhR was detected towards the mraZ binding site, nevertheless a small amount of shifted DNA was observed. No complex formation of PdhR with the binding site in front of metB gene was monitored.
Göhler et al. BMC Systems Biology 2011 5:197 doi:10.1186/1752-0509-5-197