Fig. 3.

EsaB-YFP localises to the cytoplasm and membrane. (a) EsaB-YFP is not secreted in S. aureus strain RN6390. RN6390 harbouring empty pRAB11 and the isogenic ΔesaB strain harbouring empty pRAB11 or pRAB11 encoding EsaB-YFP were cultured in TSB medium until mid-log phase and separated into cellular and supernatant fractions (sn). For each gel, 10 µl of OD₆₀₀1 adjusted cells and 15 µl of TCA-precipitated culture supernatant were loaded. Blots were probed with anti-EsxA, anti-TrxA (cytoplasmic control) and anti-GFP antisera. Cell and supernatant samples have been blotted on the same gel but intervening lanes have been spliced out. Subcellular localisation of (b) EsaB-YFP in RN6390 and an isogenic Δesx (Δ(esxA-esaG)) strain or (c) YFP in RN6390. Cells were grown aerobically in TSB to mid-log phase and fractionated as indicated in the Methods. Equivalent amounts of each fraction was probed with anti-TrxA (cytoplasmic control), anti-SrtA (membrane control), anti-EsxA and anti-GFP antisera.