Bacterial Photolithography: Patterning Escherichia coli Biofilms with High Spatial Control Using Photocleavable Adhesion Molecules.

Abstract

Biofilms are not only a leading cause of chronic infections and biofouling, but they also have a tremendous positive potential in biotechnology for biocatalysis and waste treatment. Biofilms are spatially structured communities of microbes, which exchange chemicals and communicate with each other. By spatially controlling bacterial adhesion to surfaces, and therefore the microstructure of biofilms, a promising method of understanding social interactions between bacteria and designed biofilms is developed. The bacterial photolithography approach described here allows to photopattern specific bacteria adhesion molecules, to control surface adhesion, and to guide the formation of biofilms. To do this, α-D-mannoside, which is recognized by the Escherichia coli FimH receptor, is linked to a nonadhesive polyethylene glycol surface through a photocleavable 2-nitrobenzyl linker. When a pattern of UV light in a specific shape is projected onto these surfaces, the light-exposed areas become nonadhesive and bacteria only adhere to the dark, unexposed areas in the photopattern. Bacterial photolithography enables bacterial patterning with high spatial resolution down to 10 µm without mechanical interference. Additionally, patterning biofilms with complicated geometries allows studying the importance of microscale spatial organization on the collective behavior of bacteria such as quorum sensing.