Glucose transport activity of GlcPSe mutants. Glucose uptake of GlcPSe mutants relative to wild-type, at 1 mM glucose, in E. coli JM1100 whole-cells assay. Error bars are standard deviations from 3 different experiments. Western blot of membranes extracted from cells expressing wild-type and mutants of GlcPSe is shown below. Difference in band density in the Western film was within 30%: 100%, 109%, 117%, 116%, 128%, 104%, 123% and 118%, for wild-type, R71A, R129A, N136A, N191A, R367A, R369A and E362A GlcPSe, respectively.