Figure 2
Iron-regulated and cell density-regulated performances of ironQS system. (A) Expression curves of ironQS system regulated by Fe2+ concentration. FeSO4 or iron-chelator DP was added into the medium during cultivation. (B) Expression curves of ironQS system regulated by cell density. E. tarda harboring ironQS system was cultivated via fed batch and the OD600 was maintained under 0.3 by feeding fresh iron-limited media continuously. Meanwhile a control group was carried on by cultivating the bacteria normally to a high cell density. * means a significant deviation.