Figure 2: YFP and PpIX fluorescence and ANOVA main effects for each of the 5-ALA concentrations/treatments. Absolute fluorescence of PpIX (a) displays a natural bell curve for the wide range of 5-ALA treatments. YFP fluorescence (b) was not altered except for the 5-ALA treatment levels ≥12.5 mM, suggesting that elevated 5-ALA concentrations may inhibit cell growth. The bottom figure (c) represents relative PpIX accumulation (PpIX/YFP) and demonstrates that higher levels of 5-ALA allow for more PpIX production in living cells.