Fig. 5

XrvB repressed hrpG transcription and its occupancy at the hrpG promoter region in a rich medium. a In vitro transcription assay showing that XrvB repressed the transcription of hrpG. RNA was generated from a 433-bp template DNA fragment containing hrpG promoter using E. coli RNA polymerase (RNAP) holoenzyme. A 429-bp template DNA fragment containing the rpfG promoter and a 208-bp template DNA fragment of hrpG-coding sequence were used as a control. Lane 1, template DNA alone; Lane 2, template DNA with RANP; Lanes 3–5, template DNA with RANP and 5, 10 and 20 nM His-XrvB. b ChIP and qPCR assays demonstrate that XrvB occupancy at the hrpG promoter region increased in the cells grown in the nutrient-rich medium NB. Data are presented as means ± SD (n = 3). Differences were evaluated using Student's t-test (**P < 0.01; n.s. no significance at P ≤ 0.05)