FIG 6.
The Sia system regulates cell-associated Psl production posttranslationally. (A) q-RT-PCR of pslA-containing transcripts relative to rpoD transcript levels. RNA was extracted from midlog planktonic cultures (OD600nm = 0.5). (B) Expression of the psl operon was driven by the PBAD promoter to uncouple any potential transcriptional control of the Psl promoter. These strains were analyzed for potential effects on Psl protein translation. Representative immunoblots are shown for Psl, PslB, and PslG. RNAP served as a loading control. (C) Quantification of relative Psl production calculated using blots in 6B. Psl band intensity was normalized to RNAP levels and then compared to wild-type (PAO1 PBADpsl) cell-associated Psl. (D) Adherence of psl overexpression strains to glass. Cells were incubated on a glass coverslip, rinsed and attached cells were immediately quantified by microscopy. Presented as mean and standard deviation. N, 3 biological replicates, *, P < 0.05.