FIG. 2.

Effect of oxidative stress on the viability of early-stationary-phase cells. Strains were grown overnight in BHI-FBS, and viable counts were determined in triplicate on individual cell suspensions after the initial OD₆₀₀ was adjusted to approximately 1.0, as described in Materials and Methods. In most cases error bars are too small to be seen. (A) Aerobic conditions; (B) 1 mM hydrogen peroxide; (C) 2 mM hydrogen peroxide; (D) 0.1 mM cumene hydroperoxide; (E) 0.1 mM tert-butyl-hydroperoxide. Symbols: closed triangles, wild type; open squares, tpx mutant; open diamonds, bcp mutant; open circles, tpx/bcp mutant. The data shown are from one representative experiment, but it was repeated twice with similar results.