Changes in the intrinsic fluorescence of the human erythrocyte monosaccharide transporter upon ligand binding
- 13 April 1982
- journal article
- research article
- Published by American Chemical Society (ACS) in Biochemistry
- Vol. 21 (8), 1905-1908
- https://doi.org/10.1021/bi00537a031
Abstract
The effect of ligands on the tryptophan fluorescence of the purified monosaccharide transporter from human erythrocytes was investigated. Cytochalasin B, D-glucose and ethylideneglucose quenched the fluorescence of the protein at longer wavelengths by 17, 13 and 8%, respectively. Propyl glucoside, another ligand, had no effect on the protein fluorescence. Values of the dissociation constants for cytochalasin B, D-glucose and ethylideneglucose were determined from the concentration dependence of fluorescence change; these agreed with the values obtained from the effects of these compounds upon the binding of [3H]cytochalasin B measured by equilibrium dialysis. There was no correlation between the effect of each ligand on the fluorescence of the transporter and the conformational state expected for its complex on the basis of other evidence. The fact that the quenching is greatest at longer wavelengths suggests that an exposed tryptophan residue(s), possibly located at the ligand binding sites, is the perturbed one.This publication has 6 references indexed in Scilit:
- The monosaccharide transporter of the human erythrocyte. Transport activity upon reconstitution.Journal of Biological Chemistry, 1981
- Binding of cytochalasin B to human erythrocyte glucose transporterBiochemistry, 1980
- The monosaccharide transport system of the human erythrocyte. Orientation upon reconstitutionBiochimica et Biophysica Acta (BBA) - Biomembranes, 1980
- Evidence for allosteric inhibition sites in the glucose carrier of erythrocytesBiochimica et Biophysica Acta (BBA) - Biomembranes, 1980
- Asymmetry of the hexose transfer system in human erythrocytes. Experiments with non-transportable inhibitors.The Journal of Physiology, 1978
- High affinity binding of [3H]dihydrocytochalasin B to peripheral membrane proteins related to the control of cell shape in the human red cell.Journal of Biological Chemistry, 1978