FIG 4 .

The cor mutant has a dysregulated intracellular redox environment, and its CO susceptibility can be rescued by the antioxidant α-tocopherol. (A and B) M. tuberculosis cultures were exposed to CO in vitro in quadruplicate and harvested after 0, 5, and 10 days. Small-molecule metabolites were extracted, and 145 known biochemicals were quantified using GC-MS and LC-MS. Normalized metabolite levels produced under the indicated treatment conditions, where the mean metabolite value for wild-type M. tuberculosis served as the denominator, are shown. Compared to wild-type bacteria, the cor mutant treated with CO had significantly reduced levels of mycothione (A) and NAD⁺ (B) but had increased levels of linoleate (C), linolenate (D), palmitoleate (E), and nonadecanoate (F). Differences between CO-treated M. tuberculosis Erdman and the mutant at 10 days were statistically significant. *, P < 0.05 (by Welch’s two-sample t test).