Fig 3. Effect of nitrate and anaerobic culture conditions on B. pseudomallei growth.

B. pseudomallei was inoculated in M9 minimal medium supplemented with (+NaNO₃) or without (-NaNO₃) sodium nitrate, and incubated under aerobic or anaerobic culture conditions. (A) anaerobic and (B) aerobic kinetic growth curves of B. pseudomallei cultured in the presence of nitrate. B. pseudomallei K96243 wild-type (black circle), 6H4 mutant (white circle), 6H4/pME1039 complementation (white square) strains were grown for 72 h. Every 24 h, the numbers of viable bacteria were determined by plating on LB agar for colony count. (C) Growths of B. pseudomallei K96243 wild-type (black bar), 6H4 mutant (white bar) and 6H4/pME1039 (checked bar) strains under aerobic (+O₂) and anaerobic (-O₂) culture conditions at 48 h after bacterial inoculation. Results are presented from at least three replicates with three independent experiments. Asterisks indicate statistically significant differences (P < 0.05, t-test).