Skip to main content
. 2018 Mar 7;37(8):e97825. doi: 10.15252/embj.201797825

Figure 7. CSS domain PDEs affect matrix production and architecture in deeper zones of mature macrocolony biofilms.

Figure 7

  1. Strain AR3110 and its derivatives carrying the indicated chromosomal mutations were grown in LB medium. Samples were taken during the growth of the cultures (numbers refer to hours of growth; on, overnight). Cellular CsgD levels were determined by immunoblotting.
  2. Macrocolonies of strain AR3110 and its chromosomal pdeC ASS derivative were grown on salt‐free LB (LBnoS) with the matrix dye Congo red (CR) at 28°C for 2 and 5 days.
  3. Fluorescence micrographs of vertical cryosections through the central flat regions of macrocolony biofilms of strain AR3110 and the indicated mutant derivatives were obtained after growth on salt‐free LB for 3 and 5 days at 28°C. Agar plates contained the fluorescent matrix dye thioflavin S which allows to visualize details of the extracellular matrix architecture present in the upper 45–50 μm of the macrocolonies (the entire height of Escherichia coli macrocolonies is approximately 65 μm; cells in the lower layer do not produce matrix but a mesh of entangled flagella; Serra et al, 2013a). Here, only fluorescent images are shown, the corresponding phase‐contrast and merged fluorescent/phase‐contrast images are presented in Appendix Fig S11.

Source data are available online for this figure.