FIG. 3.

Effect of growth conditions on specific levels of fnr transcripts. Wild-type F4430/73 cells were grown in regulated batch cultures (pH 7.2) under aerobic (pO₂ = 100% and 21%), microaerobic (pO₂ = 1%), and anaerobic (pO₂ = 0%) conditions at different initial ORPs (iORP) as described in Materials and Methods. Relative specific levels can be compared to the 100% value that was arbitrarily fixed for the fully aerobic condition (pO₂ = 100%). For each experiment, two measures from two independent RNA samples from the same culture taken during the mid-exponential growth phase (μ = μ_max) were analyzed in parallel. Each data point represents an average of the results for the combined experiments. RNA sampling and statistical methods were identical to those described in Table 4 and in Materials and Methods.