FIG. 1.

Effect of 4HBA on the growth of P. putida DOT-T1E. (A) Glucose-supplemented M9 minimal medium was inoculated with DOT-T1E and incubated overnight at 30°C with shaking. Thirty milliliters of the same medium containing 0 (○), 6 (●), 12 (▵), or 18 (▴) g of 4HBA/liter was inoculated with 0.3 ml of the overnight culture. (B) Bacterial cells were pregrown with glucose (0.5%, wt/vol) and 5 g of 4HBA/liter. Aliquots of this culture were used to inoculate glucose-supplemented M9 minimal medium with 0 (○), 6 (●), 12 (▵), 18 (▴), 24 (□), 30 (▪), or 36 (◊) g of 4HBA/liter. Cell growth was followed by counting CFU per milliliter on LB agar plates supplemented with rifampin (10 μg/ml). Each experiment was repeated at least three times. Results of a typical experiment from a single culture are presented. Duplicate measurements of CFU in a single experiment yielded an average standard deviation of 2 to 5%.