FIG 5.

Earlier onset of OmcB expression in Pgp4-deficient strains. (A) Western blots of lysates of L929 cells infected with C. trachomatis parental or Δpgp4 strains at 24, 28, 32, and 36 hpi, to check the expression profile of OmcB. (B and C) Immunofluorescence microscopy of L929 cells infected with C. trachomatis parental or Δpgp4 strains. Cells were fixed at 20, 24, 28, 32, or 36 hpi and stained with antibodies to OmcB (green) and MOMP (red). Expression of OmcB protein was quantified by measuring the average pixel intensity in the chlamydial inclusion within an infected cell. Scale bars, 20 μm. For each time point, 100 inclusions were analyzed; each triangle on the graph represents the average pixel intensity for one inclusion, and the horizontal line is the mean value. (D and E) Similar immunofluorescence analysis of C. muridarum parental or pgp4s strains at 16, 20, 24, 28, and 32 hpi, stained with antibodies against OmcB (red) and MOMP (green).