title: Further studies on amino acid transport in murine P388 leukemia cells in vitro. Presence of system y+.
abstract: The transport of glycine and L-lysine into murine P388 leukemia cells has been examined. Glycine transport appears to be shared by both systems A and ASC in P388 cells. Glycine transport is Na+-dependent and is effectively blocked by alpha-(methylamino)isobutyric acid, threonine and alanine but only a marginal reduction in transport is seen with 100-fold excess cold 2-aminobicyclo[2,2,1]heptane-2-carboxylic acid. System gly is not expressed in P388 cells. Lysine is largely transported by a Na+-independent, pH-insensitive system with a Km of 0.079 mM. Lysine transport is relatively unaffected by the addition of 100-fold excess cold alpha-(methylamino)isobutyric acid, 2-aminobicyclo[2,2,1]heptane-2-carboxylic acid and the anionic amino acids, L-glutamate and L-aspartate. A partial inhibition of lysine transport was observed with L-threonine and L-leucine while L-arginine and L-histidine radically decreased lysine transport. Lysine appears to be transported by a system similar to the system y+ seen in cultured human fibroblasts, Ehrlich ascites cells, and hepatoma cell lines.
mesh_terms: D000596:Amino Acids / Q000378:metabolism* / Q000494:pharmacology; D000598:Amino Acids, Cyclic; D000621:Aminoisobutyric Acids / Q000494:pharmacology; D000818:Animals; D001692:Biological Transport / Q000187:drug effects; D005998:Glycine / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D007941:Leukemia P388 / Q000378:metabolism*; D007942:Leukemia, Experimental / Q000378:metabolism*; D008239:Lysine / Q000378:metabolism; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008811:Mice, Inbred DBA; D012964:Sodium / Q000494:pharmacology
chemical_list: D000596:Amino Acids; D000598:Amino Acids, Cyclic; D000621:Aminoisobutyric Acids; C006504:2-aminobicyclo(2,2,1)heptane-2-carboxylic acid; C017911:2-(methylamino)isobutyric acid; D012964:Sodium; D008239:Lysine; D005998:Glycine