Reconstitution into liposomes of glucose active transport from the rabbit renal proximal tubule. Characteristics of the system.
This paper describes the characteristics of Na+ -dependent D-glucose transport into liposomes made from soybean phospholipids into which have been reconstituted detergent-solubilized components from the rabbit renal proximal tubular brush border membrane. Conditions for optimal and quantitative reconstitution of glucose carriers are defined. Na+ -dependent D-glucose uptake occurs via a saturable system with a Km of 0.125--0.135 mM, is responsive to the volume of the internal liposomal space, and shows 'overshoot' as seen in natural membranes. The rate of Na+-dependent D-glucose uptake and the magnitude of the 'overshoot" are proportional to the concentration of protein used in reconstitution.
D000818:Animals; D001693:Biological Transport, Active; D002352:Carrier Proteins / Q000378:metabolism; D002462:Cell Membrane / Q000378:metabolism; D002474:Cell-Free System; D005947:Glucose / Q000378:metabolism*; D007687:Kidney Tubules, Proximal / Q000378:metabolism* / Q000648:ultrastructure; D007700:Kinetics; D008081:Liposomes; D008565:Membrane Proteins / Q000032:analysis; D011817:Rabbits; D013010:Sonication; D014882:Water-Electrolyte Balance
D002352:Carrier Proteins; D008081:Liposomes; D008565:Membrane Proteins; D005947:Glucose