FIG 4.

Oligosaccharide uptake and binding by I9min_PTS cells. (a) Screening of PTS specificity by testing the binding (gray bar) and uptake (black bar) of various gluco- and fructooligosaccharides by I9min_PTS cells. Oligosaccharide concentration was determined by HPAEC-PAD after 1 h of incubation of the oligosaccharides with I9min_PTS crude membrane cell extracts (for binding) or intact cells (for uptake). (b) Kestose binding and uptake kinetics by I9min_PTS crude membrane cell extracts and intact cells, respectively. Kestose concentration in the soluble phase was determined by HPAEC-PAD; EPI cells in green, EPI membrane extracts in gray, I9min_PTS cells in blue, and I9min_PTS membrane extracts in pink. The data represent the means from three biological replicates.