Figure 3. M. tuberculosis KOR activity is tolerant to O₂ exposure.

Whole cell lysates of M. tuberculosis and B. fragilis were exposed to air at room temperature and remaining KOR (M. tuberculosis, squares; B. fragilis, circles) and POR (B. fragilis, diamonds) activities were assessed under anaerobic conditions. Percent activity remaining was calculated by dividing the rate of methyl viologen reduction at time_x by that at time₀ (% activity remaining  = rate_t = x/rate_t = 0×100). Data shown represent the mean ± standard deviation of three independent determinations.