Molecular Architecture and Assembly Principles of Vibrio Cholerae Biofilms

In their natural environment, microbes organize into communities held together by an extracellular matrix composed of polysaccharides and proteins. We have developed an in vivo labeling strategy that allows the extracellular matrix of developing biofilms to be visualized with conventional and super-resolution light microscopy. Here we show that Vibrio cholerae biofilms have three distinct levels of spatial organization: cells, clusters of cells, and collections of clusters. Subsequent multiresolution imaging of living V. cholerae biofilms revealed the complementary architectural roles of the four essential matrix constituents. RbmA provides cell-cell adhesion, Bap1 allows the developing biofilm to adhere to surfaces, and heterogeneous mixtures of Vibrio polysaccharide (VPS), RbmC, and Bap1 form the dynamic, flexible and ordered envelopes that encase the cell clusters. The ability to observe living biofilms develop with nanometer-scale precision and molecular specificity allows their fundamental construction and architectural principles to be established.View Large Image | View Hi-Res Image | Download PowerPoint Slide