FIG. 3.
Involvement of CodY in adherence and colonization. (A) In vitro adhesion of D39Δcps, D39ΔcpsΔcodY, D39ΔcpsΔpcpA, and D39ΔcpsΔcodYΔpcpA to Detroit 562 nasopharyngeal cells. The adherence of the codY mutant is given as a percentage of that of the wild type (wt). A possible model of the regulation of pcpA by CodY is shown above the histogram. For an explanation, see text. (B) Intranasal challenge with 106 CFU of the D39 wild-type or ΔcodY strain. (C) Expression of codY during experimental virulence. Transcripts of codY and gyrA were identified in bacterial RNA isolated from NPFL and BALF at 40 h postinfection. A plus sign indicates a reaction with reverse transcriptase, and m indicates the negative control (without reverse transcriptase). *, P < 0.0001 (Mann-Whitney U test); **, P < 0.05 (Student's t test).