Restoration of Active Transport of Glycosides in Escherichia coli by a Component of a Phosphotransferase System

The ability of Escherichia coli W2244 to concentrate methyl-β-thiogalactoside and methyl-α-glucoside was substantially reduced when the cells were subjected to osmotic shock. The shocked cells contained only a fraction of their normal content of a heat-stable protein, previously characterized as a component of a phosphotransferase system. When the shocked cells were incubated with the purified heat-stable protein, the ability to accumulate the glycosides was restored. The results suggest that the phosphotransferase system may be an important component of the glycoside permease systems.