HflX mediates rifampicin resistance in Brucella by downregulating the expression of RNA polymerase-associated genes

To further investigate molecular changes associated with HflX knock during rifampicin exposure, we performed label-free quantitative proteomic analysis. The WT and ΔhflX strains were cultured for three generations in the presence of 1/2 MIC rifampicin (1 μg/mL) and harvested during the logarithmic growth phase, with at least three biological replicates per group. DIA-based proteomic analysis quantified protein abundance and identified differentially expressed proteins (DEPs) (Figure 5A). Bioinformatic analyses were then conducted to evaluate enriched pathways and co-expression networks, aiming to elucidate the regulatory role of HflX in Brucella.