Extended Data Fig. 8: Exogenous peptidoglycan induces 3D biofilm formation of V. cholerae in different media and temperatures.
From: Bacteria use exogenous peptidoglycan as a danger signal to trigger biofilm formation
V. cholerae biofilm growth in our microfluidic system was measured in the presence (+) or absence (-) of 300 µg mL−1 exogenous peptidoglycan (PG), at a particular temperature (28 °C or 37 °C) and in a particular liquid medium (M9 minimal medium with 0.5% glucose, TB, LB). As growth rates strongly differ between different media and temperatures, we measured the 3D biofilm biovolume fraction with height H > 3 µm in a given growth condition at the time of maximum biofilm height, which is a time that differed between different growth conditions. The time at which the maximum biovolume fraction at heights H > 3 µm occurs is as follows: for M9, t = 7.5-13.5 h at 28 °C and 9-11 h at 37 °C; for TB, t = 3.5-4.5 h at 28 °C and 2.5-5.0 h at 37 °C; for LB, t = 2.5-4.5 h at 28 °C and 2-3 h at 37 °C). In each growth condition, the biofilm biovolume was measured at the same time for the PG-exposed and unexposed condition. In all growth conditions, PG-exposure resulted in a statistically significant enhancement of 3D biofilm formation. Bars indicate the mean of n = 3 biological replicates, error bars indicate the standard deviation and individual data points are shown. Statistical significances were calculated using a two-sided Student’s t-test; * = p < 0.1; ** = p < 0.01; *** = p < 0.001. Exact p-values are given in brackets in the figure.
