Overexpression of luxS Cannot Increase Autoinducer-2 Production, Only Affect the Growth and Biofilm Formation in Streptococcus suis
Figure 3
Production of AI-2 activity of the different strains. AI-2 activity of cell-free culture fluids in the stationary exponential phase was measured using the V. harveyi bioluminescence assay. AI-2 activity determination is expressed as relative light units and compared with the level of luminescence produced by the positive control (V. harveyi BB120). AI-2 activity of V. harveyi BB120 was set to 100% activity for normalization. V. harveyi BB120 served as a positive control and sterile THB medium as a negative control. HA9801, ΔluxS, CΔluxS, and luxS+ refer to the WT strain, the luxS mutant strain, the complementation strain, and the overexpression strain. Values are means from three independent experiments. Error bars indicate standard deviations ().
