Fig. 4

Growth of amino acid and diamine producer strains exposed to ciprofloxacin. The strains DM1729 (lysine producer) (a + b), ARG1 (arginine producer) (c + d), ORN1 (ornithine producer) (e + f) and PUT21 (putrescine producer) (g + h) were cultured to an optical density of 2 to 5 in CGXII supplemented with 1 % (w/v) glucose and ciprofloxacin was applied. Graphs on the left side (a, c, e, g) show the growth inhibition due to the addition of ciprofloxacin in concentrations of 0 μg/ml (white tirangles), 4 μg/ml (hatched squares) and 16 μg/ml (black circles). The graphs on the right side (b, d, f, h) show the concentrations of either lysine, arginine, ornithine or putrescine (black bars) and of glutamate (white bars) after the complete consumption of glucose. Values and error bars represent the mean and the standard error of duplicates