title: Differential inactivation of the "L" and "Ly+" amino acid transport systems by a sulfhydryl reagent and a photo-affinity probe.
abstract: Using a substrate-stimulated amino acid efflux system, it has been shown that the "Ly+" and "L" amino acid transport systems of mouse embryo cells in culture are differentially inhibited by parachloromercuribenzene sulfonate (PCMB-S) and the photoaffinity probe 4-fluoro-3-nitrophenylazide (FNPA). Three types of evidence support the conclusion that these transport systems are mediated by separate carrier proteins. (1) The specificity of substrate-stimulated efflux is high for each system; (2) PCMB-S inhibits L-phenylalanine and L-leucine stimulated L-[3H]phenylalanine efflux with no effect on L-lysine stimulated L-[3H]lysine efflux, and (3) the photo-affinity probe FNPA inhibits L-lysine efflux with little effect on the L-phenylalanine-stimulated efflux.
mesh_terms: D002731:4-Chloromercuribenzenesulfonate / Q000494:pharmacology*; D000596:Amino Acids / Q000378:metabolism*; D001386:Azides / Q000494:pharmacology*; D001692:Biological Transport; D002460:Cell Line; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism; D005464:Fluorobenzenes / Q000494:pharmacology; D007700:Kinetics; D008239:Lysine / Q000378:metabolism; D009942:Organometallic Compounds / Q000494:pharmacology*; D010042:Ouabain / Q000494:pharmacology; D010649:Phenylalanine / Q000378:metabolism / Q000494:pharmacology; D012964:Sodium / Q000494:pharmacology
chemical_list: D000596:Amino Acids; D001386:Azides; D005464:Fluorobenzenes; D009942:Organometallic Compounds; D010649:Phenylalanine; D010042:Ouabain; D002731:4-Chloromercuribenzenesulfonate; D012964:Sodium; D008239:Lysine