Fig. 3From: The QseB/QseC two-component system contributes to virulence of Actinobacillus pleuropneumoniae by downregulating apf gene cluster transcriptionElectrophoretic mobility shift assay of interaction between QseB and the promoter regions. Different amount of purified QseB protein was incubated with DNA fragment of promoter region of apf (a), pilM (positive control) (b) and glpK (negative control) (c)Back to article page