Figure 5. Effect of iron availability on T. gammatolerans Cd tolerance.

Cd susceptibility was analyzed in ASW-AA-Cyst medium (black line) or in modified ASW-AA-Cyst media supplemented with: 200 µM DTPA (metal chelator, grey line), 100 µM iron (green line), 1 mM Cd (yellow line), 1 mM Cd and 100 µM iron (orange line); 1 mM Cd and 200 µM DTPA (blue line); 1 mM Cd and 200 µM DTPA and 100 µM iron (brown line). The effect of iron availability on Cd tolerance was investigated in each culture medium inoculated with 10⁷ cells/mL and incubated at 85°C on a reciprocal shaker. Cell densities were scored over time using a Thoma counting chamber. The values are the mean of three independent cultures (SD ≤10%).