Figure 4.

HflX complements the deficiency of RRF. A, spotting assay of the RRF-depleted strain and the hflX knockout harboring the indicated empty and complementation plasmids. Data are representative of three independent experiments. Cells were adjusted to an A₆₀₀ of ∼0.2 and were serially diluted and spotted (3 μl/spot) on TSB-agar plates, then grown overnight at 37 °C to determine cell viability. The expression of hflX and frr in trans restored the growth of the RRF-depleted strain in the absence of anhydrotetracyline (aTc). B, expression of RRF in S. aureus TSB cultures with and without aTc. Western blots were performed using anti-RRF at 1:4,000 dilutions.