Fig. 4
Effects of different inducers on cell physiology of GFP-producing cells. A Amino acid consumption determined by HPLC analysis of culture supernatants taken at the indicated post-induction times. B SDS-PAGE analysis of protein extracts from samples taken at the end of induction. M: molecular weight marker, T0: total protein fraction before the induction, T: total protein fraction, S: soluble protein fraction, I: insoluble protein fraction. C Cell viability determined by flow cytometry analysis after labeling dead cells with propidium iodine. D SOD specific activity measured by McCord and Fridovich assay on the soluble protein fraction extracted from samples taken at the indicated times. The mean values of three (A, C) or four (D) independent measurements are shown with error bars indicating standard deviations. Statistical analyses were performed using unpaired two-tailed Student’s t-test, n.s.: not significant p > 0.05, *p < 0.05, **p < 0.01, ***p < 0.001