Single microcolony diffusion analysis in Pseudomonas aeruginosa biofilms.

摘要: The influence of the biofilm matrix on molecular diffusion is commonly hypothesized to be responsible for emergent characteristics biofilms such as nutrient trapping, signal accumulation and antibiotic tolerance. Hence quantifying coefficient important determine whether there an microenvironment mobility molecules. Here, we use single plane illumination microscopy fluorescence correlation spectroscopy (SPIM-FCS) obtain 3D maps with micrometre spatial millisecond temporal resolution entire Pseudomonas aeruginosa microcolonies. We probed how properties size charge well microcolony depth fluorescently labelled dextrans inside biofilms. 2 MDa dextran showed uneven penetration a reduction in suggesting that acts sieve. Its was negatively correlated microcolony. Positively charged molecules positively tobramycin preferentially partitioned into remained mobile microcolony, albeit reduced coefficient. Lastly, measured changes upon induction dispersal detected increase before any loss biomass. Thus, change proxy detect early stages dispersal. Our work shows are very sensitive physiological biofilms, viz. However, this study also diffusion, mediated by matrix, does not account high level tolerance associated