Growth and viability in pure and mixed cultures. Species-specific cell concentrations and viability were determined over a cultivation period of 32 h by qT-RFLP and flow cytometry, respectively. Open symbols represent data from pure cultures and filled symbols from mixed culture. Left: Dynamics of log10-transformed species-specific cell concentrations of (A) P. aeruginosa, (C) B. cepacia, and (E) S. aureus. Right: Dynamics of relative frequencies of (B) viable and dead cells of P. aeruginosa, (D) viable and dead cells of B. cepacia and (F) viable, damaged and dead cells of S. aureus. Relative frequencies of viability subpopulations were determined based on all SYBR Green I and PI fluorescence positive events in the respective species gate. Subpopulations were defined as gated in plots shown in Figure 2. Error bars represent standard deviation of two (*) or three biological replicates.