Fig. 1.
Evaluation of SYBR staining intensity in S. epidermidis bacteria upon the shift from the biofilm to the planktonic mode of growth. Bacteria obtained from low dormancy 48 h biofilms were diluted in fresh TSB (1×108 cells ml−1) and allowed to grow in the planktonic form for 6 h. Simultaneously, parallel cultures of 48 h biofilms were allowed to grow for an additional 6 h in fresh TSB. At the indicated time points, bacteria obtained from each culture were stained with SYBR and PI (5 µg ml−1) and the bacterial fluorescence was determined by flow cytometry analysis. Values shown within the bi-parametric dot plots (SYBR vs PI) represent the MFI of the SYBR or PI signal±sd from bacteria within the respective flow cytometry analysis region. Arrows within the dot plots represent the direction of the shift in the bacterial MFI due to SYBR/PI staining between assessed time points. Results are a representative example of two independent experiments that generated concordant results.