FIG 5.

CRC-associated microbe B. fragilis and E. coli responses to aspirin. Growth of B. fragilis strains BF638R and ETBF086 in basal medium (BM) or BM supplemented with 2.5 mM aspirin as determined by optical density (A) and growth yield (CFU per ml; B) after anaerobic growth for 24 h at 37°C. Growth of E. coli strains BW25113, LF82, and CCR20 and ETBF086 in LB or LB supplemented with 2.5 mM aspirin as determined by optical density (C) and growth yield (CFU per ml; D) after anaerobic growth for 24 h at 37°C. All data represent the mean ± SEM for at least 6 cultures. Growth curves were analyzed by two-way repeated measures ANOVA with post hoc Dunnett’s test, and growth in 1 mM aspirin was significantly different from control medium at P values of <0.05 for each of the following strains beginning at the indicated time points: BF638R (6 h), ETBF086 (5.5 h), BW25113 (3 h), LF82 (3.5 h), and CCR20 (3.5 h). Growth yield analysis was performed by Mann-Whitney test; **, P < 0.01.