Effect of Metabolic Activity of the Glucose Permease of Bacterial Cells

The experiments all point to a difference be tween the glucose (alpha methyl glucoside) ac cing system of both S. typhimurium and E. coli and the beta-galactoside and galatose ac cumulating systems of E. coli. Active respira tory activity accompanied by oxidative phosphory lation depresses rather than enhances the steady state level of alpha MG accumulated within the cells. The level attained during the oxidation of an exogenously supplied substrate can be raised by the addition of dinitrophenol or azide at suitable concentrations. Furthermore, the alpha MG accumulation is greater when the cells depend for their energy supply on endogenous respiration or on the anaerobic fermentation of an exogenous substrate rather than on the active oxidation of such a substrate in the absence of poisons. (Author)