In this study, researchers from AIMES-Center for the Advancement of Integrated Medical and Engineering Sciences, Karolinska Institutet and KTH Royal Institute of Technology in Sweden, investigated the biofilm formation process in uropathogenic Escherichia coli (UPEC) and determined how extracellular matrix (ECM) components like curli and cellulose contribute to biofilm maturation. They aimed to understand the spatial and temporal dynamics of biofilm formation, particularly focusing on UPEC 12, a strong biofilm producer.
The researchers used EbbaBiolight 680 to stain the extracellular matrix of biofilm. EbbaBiolight was added to the LB-agar before the plate cast. Automated live imaging and 2-photon microscopy were performed on UPEC colonies growing on EbbaBiolight supplemented agar helped map biofilm formation across different regions of the colony.
The study concluded that coordinated expression of curli and cellulose is essential for biofilm formation, with curli forming radial structures that contribute to biofilm architecture. These findings provide new insights into the biofilm lifestyle of UPEC and its role in urinary tract infections, offering potential targets for future treatment strategies.
Image: Non-interventional intravital imaging of native UPEC12-GFP biofilm using intravital 2-photon microscopy of native UPEC12-GFP biofilm grown at 37 °C. The spatial distribution of bacterial cells (green) and Ebba680-labeled curli (red) are shown in 3D reconstructions from obtained Z-stacks. (A) 3D montage showing the xy plane of a section of the biofilm with the morphologically distinct central, intermediate, and outer regions. (B) Surface rendered image of the Ebba680-labeled curli signal (red) of the boxed region in (A), shown as an axially tilted image. Scale bar = 0.1 mm. Image from Figure 7 AB by Zhang et al. (2024) Biofilm, 8(1), 100212 (CC BY 4.0).