Figure 8.

Serum differentially regulates the expression of the QS regulatory genes during early and late phases. PAO1 was grown in either LB or LB/S. Samples were obtained at early and late phases and the level of expression was determined by qRT-PCR analysis. (A) At early phase, serum reduced the expression of the PAO1 QS-positive regulator vqsR, but enhanced the expression of the QS-negative regulators mvaT and rsmA. (B) At late phase, serum enhanced the expression of the QS-positive regulators vqsR, gacA, and vfr. Values represent the means of three independent experiments ± SEM; ***P < 0.001, **P < 0.01, *P < 0.05.