Fig. 8.

The GbaA regulon confers resistance under disulfide stress (diamide, allicin) and electrophiles (NEM, MG) in S. aureus. For survival assays, S. aureus COL WT, the gbaA, gbaB and SACOL2592-90 deletion mutants and gbaA, gbaB complemented strains were grown in RPMI medium until an OD₅₀₀ of 0.5 and treated with 5 mM diamide (A), 0.5 mM allicin (B), 0.3 mM NEM (C), 2 mM MG (D) and 100 μM MHQ (E). CFUs were counted after plating 100 μl of serial dilutions onto LB agar plates after 2 and 4 h of stress exposure. The survival of treated cells was normalized to the untreated control, which was set to 100%. The results are from four biological replicates. Error bars indicate the standard deviation (SD) and the statistics was calculated using a Student's unpaired two-tailed t-test. Symbols are: *p ≤ 0.05, **p ≤ 0.01 and ***p ≤ 0.001.