Fig. 5

Production of 5-hydroxyectoine in response to the presence of different ectoine concentrations in the growth medium. The E. coli strain FF4169 containing either pMP41 (ectD gene from P. stutzeri A1501) (a, c), or the empty vector pASK-IBA3 (b, d) were grown in shake flasks containing MMA, ampicillin and 0.4 M NaCl, in the presence of various ectoine concentrations with 20 ml culture volume. After induction of ectD expression through the addition of AHT to the medium, the cells were further grown for 24 h, and the ectoine (grey) and 5-hydroxyectoine (red) content of the cells (a, b) or that of the supernatant (c, d) was subsequently assessed via HPLC analysis. The values shown are the means and standard deviations of two independent cultures