Interfaces and spatial confinement are known to affect motile behavior of bacteria in more artificial settings such as microfluidic systems. Cells in a bacterial colony move in confined space surrounded by boundaries between gas, liquid, and solid phases. For example, in many occasions bacterial colonies are sessile and their expansion is driven by growth rather than by cell motility, but these sessile colonies normally preserve a subpopulation of motile cells for reasons that are not well understood 17.Ĭolony mode of bacterial growth on solid substrates (e.g., food products and solidified nutrient agar) is a common experimental approach to study structured microbial communities 11 and is closely related to biofilm development 23, 24. However, except in circumstances where motile cells drive colony expansion (e.g., bacterial swarming 8, 10, 22), the physiological functions of motile subpopulations in bacterial communities are largely unclear.

Motile subpopulations in microbial communities are believed to be important to dispersal 18, 19, quest for food 20, and material transport 21. Heterogeneous populations, including motile and non-motile populations, often coexist in bacteria communities 17. In addition, as a type of active matter, microbial communities have provided model systems for the research of biological self-organization and complex fluids 12– 16. Understanding the physiology of these structured microbial communities is not only essential to the treatment of chronic infections, but also important to industrial applications, such as bioremediation, anti-biofouling and food hygiene. The multicellular lifestyle is key to the prospering of microbes in diverse habitats as it confers high resistance to various environmental stresses 7– 11. Microbes commonly live in structured communities that play important roles in human health and ecology 1– 5, such as biofilm aggregates during chronic infections 6, commensal microbiome in animal guts, microbial mats in river beds or ocean floors, and bacterial colonies in soils or food products 5.

Load proteus 6.9 with crack