Mechanical signatures of microbial biofilms in micropillar-embedded growth chambers

Biofilms are surface-attached communities of microorganisms embedded in an extracellular matrix and are essential for the cycling of organic matter in natural and engineered environments. They are also the leading cause of many infections, for example, those associated with chronic wounds and implanted medical devices. The extracellular matrix is a key biofilm component that determines its architecture and defines its physical properties. Herein, we used growth chambers embedded with micropillars to study the net mechanical forces (differential pressure) exerted during biofilm formation in situ. Pressure from the biofilm is transferred to the micropillars via the extracellular matrix, and reduction of major matrix components decreases the magnitude of micropillar deflections. The spatial arrangement of micropillar deflections caused by pressure differences in the different biofilm strains may potentially be used as mechanical signatures for biofilm characterization. Hence, we submit that micropillar-embedded growth chambers provide insights into the mechanical properties and dynamics of the biofilm and its matrix.Ministry of Education (MOE)National Research Foundation (NRF)Published versionWe acknowledge financial support from the Singapore Centre for Environmental Life Sciences Engineering (SCELSE), whose research is funded by the National Research Foundation Singapore, Ministry of Education Singapore, Nanyang Technological University and National University of Singapore, under its Research Centre of Excellence program. We also acknowledge Singapore MIT Alliance for Research and Technology’s research program in BioSystems and Micromechanics supported by the National Research Foundation Singapore