Figure 1

Altering the ratio of GFP:mCherry S. aureus influences resulting bacterial mass formation. (a) Diagram showing experimental overview. (b–h) RAW264.7 macrophages were infected with different ratios of GFP and mCherry marked S. aureus (total MOI 5). The number of single- or dual-colour bacterial masses detected at 25 h post-infection is indicated, error bars show mean values ± standard deviation, each data point represents a well. Ratios (GFP:mCherry): (b), 1:1 ratio (n = 4); (c) 1:2 ratio (n = 4); (d) 2:1 ratio (n = 4); (e) 1:5 ratio (n = 3); (f) 5:1 (n = 3); (g) 1:10 (n = 3); (h) 10:1 (n = 3), *p < 0.05, **p < 0.005, ***p < 0.0005, ****p < 0.0001, as determined using a Kruskal–Wallis test with Dunn’s post-hoc test. GFP (cyan), mCherry (magenta), media control (grey), dual (black). i, Comparison between expected (open circles) and observed (closed circles) mass numbers for ratio data presented in (c–h), with expected plots calculated based on 1:1 ratio data from b, dotted line depicts difference between expected and observed values. (j–k), Comparison between number of total single-colour (grey) and dual-colour masses (black) for ratio data presented in (b–h): (j), summary of average plots for (b–h).