FIG. 3.
Resistance of R. capsulatus SB1003, SB grxC, SB trxC grxC, SB gshB, SB trxC gshB, SB grxC gshB, SB grxC(pRKgrxC), and SB gshB(pRKgshB) to hydrogen peroxide (A) and diamide (B) in the zone inhibition assay. A 0.4-ml portion of a culture in exponential growth phase (OD660 = 0.35) was mixed with prewarmed (42°C) top agar (0.7% agar) and layered onto malate minimal salt medium plates. After the top agar had hardened, 5.5-mm-diameter filter paper disks containing 5 μl of oxidative agents as indicated were placed on the plates. Mean values of the diameter (millimeters) of the inhibition zones plus the standard deviations from four different experiments are displayed.