Isolation of the sodium-dependent d-glucose transport protein from brush-border membranes.
Rabbit kidney brush-border membrane vesicles were exposed to bacterial protease which cleaves off a large number of externally oriented proteins. Na+-dependent D-glucose transport is left intact in the protease-treated vesicles. The protease-treated membrane was solubilized with deoxycholate and the deoxycholate-extracted proteins were further resolved by passage through Con A-Sepharose columns. Sodium-dependent D-glucose activity was found to reside in a fraction containing a single protein band of Mr approximately equal to 165 000 which is apparently a dimer of Mr approximately or equal to 85 000. When reconstituted and tested for transport, this protein showed Na+-dependent, stereo-specific and phlorizin-inhibitable glucose transport. Transport activity is completely recovered and is 20-fold increased in specific activity. A similar isolate was obtained from rabbit small intestinal brush-border membranes and kidneys from several other species of animals.
D000818:Animals; D002352:Carrier Proteins / Q000302:isolation & purification*; D002417:Cattle; D002846:Chromatography, Affinity; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005947:Glucose / Q000378:metabolism*; D006041:Goats; D007421:Intestine, Small / Q000648:ultrastructure; D007672:Kidney Cortex / Q000648:ultrastructure*; D008081:Liposomes / Q000378:metabolism; D008871:Microvilli / Q000032:analysis; D008970:Molecular Weight; D009004:Monosaccharide Transport Proteins; D010206:Papain / Q000378:metabolism; D011817:Rabbits; D012964:Sodium / Q000378:metabolism*
D002352:Carrier Proteins; D008081:Liposomes; D009004:Monosaccharide Transport Proteins; D012964:Sodium; D010206:Papain; D005947:Glucose