title: Transport of 2-methyl-4-amino-5-hydroxymethylpyrimidine by Salmonella typhimurium.
abstract: The transport of 2-methyl-4-amino-5-hydroxymethylpyrimidine (MAHMP) by Salmonella typhimurium was studied using synthetic [methyl-3H3]MAHMP. It was found that an active transport system existed for MAHMP, having Km of 0.07 microM and Vmax 45 nmol.min-1.(g dry wt. cells)-1, that required glucose as a source of energy and was pH and temperature dependent. Uptake was inhibited by cyanide, azide, N-ethylmaleimide, 2,4-dinitrophenol and carbonyl cyanide m-chlorophenylhydrazone. Uptake was also weakly inhibited by oxythiamine, but not by thiamine, 2-methyl-4-amino-5-aminomethylpyrimidine, or 4-amino-5-hydroxymethylpyrimidine, indicating that the transport system is specific for MAHMP.
mesh_terms: D001693:Biological Transport, Active / Q000187:drug effects; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D011743:Pyrimidines / Q000378:metabolism*; D012486:Salmonella typhimurium / Q000378:metabolism*; D013997:Time Factors
chemical_list: D011743:Pyrimidines; C012068:toxopyrimidine