Purification and reconstitution of a 75-kilodalton protein identified as a component of the renal Na+/glucose symporter.
A 75-kilodalton (kDa) protein was purified from solubilized renal brush border membranes by using high-pressure liquid chromatography (HPLC) and preparative sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Functional and immunological properties identified the 75-kDa protein as a component of the Na+/glucose symport system. The purified protein was specifically recognized by a monoclonal antibody that functionally interacts with the Na+/glucose symporter. Na+-dependent phlorizin binding activity was associated with fractions containing the 75-kDa protein during HPLC fractionation on the anion exchanger Mono-Q and was greatly increased after reconstitution into egg yolk phosphatidylcholine vesicles. The final purified preparation contained glucosamine and a blocked N-terminus.
Department of Biochemistry and Molecular Biology, University of Texas Medical School, Houston 77225.
J S
JS
Wu
J E
JE
Lever
D000818:Animals; D000911:Antibodies, Monoclonal; D000936:Antigen-Antibody Complex; D007672:Kidney Cortex / Q000378:metabolism*; D007700:Kinetics; D046911:Macromolecular Substances; D008871:Microvilli / Q000378:metabolism; D008970:Molecular Weight; D009004:Monosaccharide Transport Proteins / Q000276:immunology / Q000302:isolation & purification* / Q000378:metabolism; D010695:Phlorhizin / Q000378:metabolism; D013552:Swine
D000911:Antibodies, Monoclonal; D000936:Antigen-Antibody Complex; D046911:Macromolecular Substances; D009004:Monosaccharide Transport Proteins; D010695:Phlorhizin