Ute Römling

Biofilm formation the build up of multicellular, often surface-associated, communities of autonomous cells, is the natural mode of growth of up to 80% of microorganisms living on this planet. Their tolerance against multiple environmental stresses makes biofilms refractory towards antimicrobial treatment strategies and the actions of the immune system. But how did biofilm formation arise? Here, I argue that the origin of the biofilm lifestyle has its foundation in fundamental surface-triggered chemical reactions and energy preserving mechanisms that enabled the development of life on earth. Subsequently, prototypical biofilm formation has evolved and diversified concomitantly in composition and regulation with the expansion of prokaryotic organisms and their radiation by occupation of diverse ecological niches. This ancient origin of biofilm formation thus indicates that harnessing conditions have been the rule rather than the exception in microbial life, while upon the emergence of the association of microbes with higher organisms including recent human pathogens, although being in a nutritional and stress-protecting heaven, some of these basic mechanisms of biofilm formation have been surprisingly conserved to promote sustained survival in new environments.