FIG. 2.

PA5471 stimulates mexXY expression in the absence of antibiotics. The expression of PA5471 (A), mexX (B), and rpoD (C) was assessed in P. aeruginosa strain K767 carrying pUCP20T (lane 1) or pYM010 (pUCP20T::PA5471), using semiquantitative RT-PCR. The rpoD reaction served as an internal control that ensured that equal amounts of RNA were employed in all of the RT-PCRs shown. The PCR portion of the reactions was carried out for 15 (top panel) and 17 (bottom panel) cycles for PA5471, 19 (top panel) and 21 (bottom panel) cycles for rpoD, and 30 (top panel) and 32 (bottom panel) cycles for mexX. Data are representative of two or three replicates.