FIG. 8.

Growth of M. smegmatis ndh mutants at permissive temperature (30°C) with and without INH. The ndh mutants were grown at 30°C to mid-log phase and diluted to an OD₆₀₀ of ≈0.05. The diluted cultures (10 ml) were added to four square bottles, and to each square bottle was added 0, 25, 50, or 100 μg of INH/ml. The cultures were incubated while shaking at 30°C. The growth of the cultures was followed spectrophotometrically by measuring the OD₆₀₀. To simplify the figures, only one mutant is shown per group. (A) Typical growth curve for M. smegmatis ndh mutants not affected by INH, such as mc²2374, mc²2376, mc²2378, mc²2379, mc²2380, mc²2381, and mc²2384 (mutant shown is mc²2384). (B) Typical growth curves of M. smegmatis ndh mutants with a growth rate delayed by INH, such as mc²2375, mc²2377, mc²2382, mc²2383, mc²2385, mc²2386, mc²2387, and mc²2388 (mutant shown is mc²2377).