Fig. 2

Expression profile of Francisella noatunensis subsp. orientalis putative T6SS genes, iglA, iglB, pdpB, vgrG, and dotU when exposed to different pHs for 1 h (a), 6 h (b) or 24 h (c). Gene expression was determined by qRT-PCR, using relative quantification. Gene expression was normalized by the housekeeping gene ftsZ. Zero hour of growth at pH 7 was used as calibrator (value =1). The error bars represent the standard deviation of nine replicate samples from three independent experiments. Statistically significant differences relative to 0 h at pH 7 are marked (*, P < 0.05)