Renal sugar transport in the winter flounder. III. Two glucose transport systems
| Autor: | George R. Dubyak, Arnost Kleinzeller, P. M. Griffin, Elizabeth M. McAvoy, James M. Mullin, R. Rittmaster |
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| Rok vydání: | 1977 |
| Předmět: |
Chemical Phenomena
Physiology Stereochemistry Phloretin chemistry.chemical_element Deoxyglucose Kidney Ring (chemistry) Oxygen chemistry.chemical_compound Animals Xylose biology Chemistry Hydrogen bond Fishes Glucose transporter Methylglucosides Biological Transport biology.organism_classification Glucose Phlorhizin Pyranose Covalent bond Winter flounder Mannose |
| Zdroj: | Scopus-Elsevier |
| ISSN: | 1522-1466 1931-857X |
| DOI: | 10.1152/ajprenal.1977.232.3.f227 |
| Popis: | Teased renal tubules of the winter flounder (Pseudopleuronectes americanus) were employed to investigate the structural requirements for two pathways of D-glucose transport which take place preponderantly across the basal (antiluminal) face of renal cells. 1) An inhibition analysis of the equilibrating, Na-independent and phlorizin-sensitive transport of the nonmetabolizable methyl-alpha-D-glucoside (0.1 and 0.5 mM), with 20 glucose analogs (5 mM), was employed to establish the structural requirements for the substrate-carrier interaction: a (pyranose) ring, oxygen, or F at C1, C2-OH, C3-OH, and C4-OH (all axial, 1C model). Some interaction may also occur at C6-OH. D-Glucose shares this transport system. Hydrogen bonding between the oxygens and the carrier is suggested. 2) The phloretin- and phlorizin-sensitive, ouabain-insensitive transport of D-glucose, 2-deoxy-D-glucose, and D-mannose is associated with considerable phosphorylation. The three sugars mutually compete for a shared transport site. The specificity pattern characterizing the transport system defines the following structural requirements: a (pyranose) ring, a free C1-OH, C3-OH, and C4-OH (both axial) and possibly C6-OH. Hydrogen bonding between the carrier and the oxygens at C3, C4, and C6, and covalent bonding at C1 is suggested. |
| Databáze: | OpenAIRE |
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