FIG. 5.

Salt stress induction of H⁺-PPase in R. rubrum. Cultures grown under anaerobic phototrophic (A) or aerobic heterotrophic (B) conditions up to the mid-exponential phase were then supplemented with either water or a concentrated NaCl solution. In each case, Northern (upper panels) and Western (middle panels) blot analyses were performed after 12 h of salt treatment. Growth during this time interval is also shown as bar histograms (lower panels). Open bars, onset of growth; dotted bars, growth after 12 h of treatment. The concentration of salt added (up to 1 M) is indicated in each case.