Figure 4. 3D CLSM images were captured from the gfp-labeled S. maltophilia wild-type (left), rpfF mutant strain (middle) and the rpfF mutant strain supplemented with 100 µM DSF (right).

While the wild-type strain formed structured, surface-covering cell architecture with a particular texture consisting of several cell layers, the rpfF mutant strain constructed an unstructured and unconnected monolayer film of cells. The rpfF mutant strain supplemented with 100 µM DSF (cis-Δ2-11-methyl-Dodecenoic Acid), however, formed the same structure observed for the wild-type. gfp-labeled wild-type and rpfF mutant strain cultures as well as the rpfF mutant strain culture supplemented with 100 µM synthetic DSF molecule were grown in LB medium up to OD₆₀₀ of 1. The cultures were then filled into the chambers of the Lab-Tek® II CC2™ Chamber Slide™ System and incubated at 37°C for three days. To capture the microscopic images a Leica TCS SPE confocal laser scanning microscope was used. The confocal stacks were acquired with the Leica ACS APO 63X OIL CS objective (NA: 1.30) by applying a z-step of 0.4–0.9 µm. The 3D analysis of the CLSM stacks was performed using the software Imaris 7.0. The assay was performed at least four times.