Fig. 6.

Competitive inhibition of 3-OMG uptake by unlabeled glucose (d-Glc) is observed only when initial rates of 3-OMG uptake are measured. Uptake of labeled 3-OMG was measured for the indicated times and at the indicated temperatures. Unlabeled d-glucose (5 mM) was omitted from or included in the uptake medium (uptake). Unlabeled d-glucose (5 mM) was also absent or included in the cell suspension for 5 min prior to initiation of uptake measurements (preincubation). Values are means ± SE of 3 independent experiments, each performed in triplicate and expressed relative to uptake measured over 10 min at 24°C in the absence of d-glucose.