Promoter activity during aerobic growth, hypoxia, and reaeration in <i>M. tuberculosis.</i>

<p>A) <i>M. tuberculosis</i> transformants harbouring P₂₇₈ were grown in aerobic culture. Results are the average activity of three transformants against average OD₅₈₀. A significant difference, measured by the student’s t-test (unpaired, two sided), compared to promoter activity at OD₅₈₀ = 0.15 is marked by an *(p<0.05). B) P₂₇₈ promoter activity in the Wayne model of hypoxia. <i>M. tuberculosis</i> liquid cultures were inoculated to a theoretical starting OD₅₈₀ of 0.004 in DTA medium. A significant difference compared to activity at day 0 is marked by an *(p<0.05) using the student’s t-test (unpaired, two sided). C) P₂₇₈ promoter activity after reaeration. Long term hypoxic cultures (12 weeks) were used to inoculate medium and grown in aerobic rolling cultures. Cell-free extracts were prepared once the cultures reached an OD₅₈₀ of 0.3. Results are the average activity of three independent transformants assayed in duplicate ± standard deviation. Activity is given in Miller Units- measured as nmol of O-nitrophenol produced per min per mg of protein.