Photoaffinity labeling of the human erythrocyte monosaccharide transporter with an aryl azide derivative of D-glucose.

Shanahan MF, Wadzinski BE, Lowndes JM, Ruoho AE
J Biol Chem. 1985 260 (20): 10897-900

PMID: 4040910

A photoreactive, radioiodinated derivative of glucose, N-(4-iodoazidosalicyl)-6-amido-6-deoxyglucopyranose (IASA-glc), has been synthesized and used as a photoaffinity label for the human erythrocyte monosaccharide transporter. Photoinactivation and photoinsertion are both light-dependent and result in a marked decrease in the absorption spectra of the compound. When [125I]IASA-glc was photolyzed with erythrocyte ghost membranes, photoinsertion of radiolabel was observed in three major regions, spectrin, band 3, and a protein of 58,000 daltons located in the zone 4.5 region. Of the three regions which were photolabeled, only labeling of polypeptides in the zone 4.5 region was partially blocked by D-glucose. In the non-iodinated form, N-(4-azidosalicyl)-6-amido-6-deoxy-glucopyranose inhibited the labeling of the transporter by [125I]IASA-glc more effectively than D-glucose. The ability to synthesize this [125I]containing photoprobe for the monosaccharide transporter at carrier-free levels offers several new advantages for investigating the structure of this transport protein in the erythrocyte.

MeSH Terms (11)

Affinity Labels Azides Blood Glucose Carrier Proteins Electrophoresis, Polyacrylamide Gel Erythrocyte Membrane Glucosamine Humans Iodine Radioisotopes Molecular Weight Monosaccharide Transport Proteins

Connections (1)

This publication is referenced by other Labnodes entities: