Bacterial behavior and biofilm formation in the presence of optical traps

In response to a hostile environment, some bacteria form a biofilm by secreting a glue-like matrix called extracellular polymeric substance (EPS) that functions as a physical barrier. In this work, we study the biofilm formation of Bacillus subtilis within minimal biofilm-promoting media (MSgg) and how optical trapping affects bacteria aggregation and biofilm formation. We demonstrate that a laser with a low absorbent wavelength can be used to manipulate biofilm and aggregate bacteria without causing significant photodamage. Whereas, even at low power, a laser with a high absorbent wavelength disrupts biofilm formation and causes significant photodamage to trapped bacteria.