Expression analysis of trxHEp. A Expression of trxHEp under different conditions. RT-qPCR was performed with total RNA extracted from Edwardsiella piscicida TX01 cultured in normal LB medium (control, pH = 7), in hydrogen peroxide condition (normal LB medium with H2O2), in acid condition (pH = 5), in iron limitation condition (with the iron chelator 2,2′dipyridyl, Dp), Expression level of trxHEp in normal LB medium was set as 1. B RT-qPCR was performed with total RNA extracted from TX01 incubated with or without (control) FG cells. Expression level of trxHEp without FG cells was set as 1. C RT-qPCR was performed with total RNA extracted from wild type TX01 and fur mutant strain cultured in normal LB medium. Expression level of trxHEp in wild type TX01 strain was set as 1. D DH5α/pSH510/pTFur and DH5α/pSH510/pT were streaked and cultured on LB plate with X-gal, kanamycin, and ampicillin. Data are presented as mean ± SEM (N = 3). N, the number of times the experiment was performed. **P < 0.01.