FIG. 1.

HMW EPS I production of different R. meliloti strains. The HMW EPS I production of the R. meliloti Rm2011 wild-type strain (WT), the exoP* mutant RmΔP*1 (exoP*), and strain RmΔexoP carrying the plasmids pExoP-R443L (R443L) and pExoP-P457S (P457S) in GMS medium supplemented with sodium chloride to osmolarities of 0.09 to 0.48 osmol/liter is shown. The percentage of the HMW EPS I fraction in relation to the total amount of EPS I is given. Values are averages of at least five independent experiments. Standard deviations were equal to or less than 4%.