Influence of iron supplementation to the minimal medium. (A) Dependency of the plasma survival rate on the intracellular iron concentration in E. coli wild type. Amounts of FeSO4 [µM] added to the medium are indicated next to each data point. (B) Enzyme activity of malate dehydrogenase (MDH), aconitase (ACN), fumarase (FUM), and succinate dehydrogenase (SDH) after µAPPJ treatment. E. coli wild type supplemented with 10 µM Fe2+ were left untreated (gray, set to 1.0), exposed to gas flow (blue), or treated with plasma (orange). Residual enzyme activity was determined either directly after treatment (t0, dark bars) or after incubation at 37°C for 20 min (t20, light bars). Averages and standard deviations represent three independent biological replicates.