Mutation frequencies of <i>S. aureus</i> biofilms grown under constant flow.

<p>Mutation frequencies of planktonic and biofilm cultures (grown in the Sorbarod model) of <i>S. aureus</i> SH1000 (<b>A</b>) and <i>S. aureus</i> UAMS-1 (<b>B</b>) determined by rifampicin and mupirocin selection. P indicates planktonic cultures and 96 h and 144 h indicate biofilm (B) incubation time. Biofilm cultures were incubated in the presence (+HP) and absence (−HP) of 4% (v/v) human plasma. Data are based on three experimental replicates. Error bars indicate 95% confidence intervals.