title: Transport of fatty acid is obligatory coupled with H+ entry in spheroplasts of Escherichia coli K12.
abstract: Transport of palmitate by spheroplasts of Escherichia coli K12 was studied. [14C]Palmitate was accumulated in spheroplasts approximately 1700-fold over the extracellular concentration of unbound [14C]palmitate. Uptake of [14C]palmitate was inhibited to 13% by addition of H+ uncoupler carbonyl cyanide-m-chlorophenylhydrazone (CCCP). Spheroplasts exhibited the uptake of 9-aminoacridine depending on the addition of palmitate to the incubation mixture. The rate of [14C]palmitate uptake by the spheroplasts pre-equilibrated in a buffer at pH 7.5 or 8.0 significantly increased in comparison with the spheroplasts pre-equilibrated in a buffer at pH 7.0 when the spheroplasts were incubated at an external pH of 7.0.
mesh_terms: D001693:Biological Transport, Active / Q000187:drug effects; D002258:Carbonyl Cyanide m-Chlorophenyl Hydrazone / Q000494:pharmacology; D004926:Escherichia coli / Q000378:metabolism*; D005227:Fatty Acids / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D010168:Palmitates / Q000378:metabolism; D011522:Protons; D013104:Spheroplasts / Q000378:metabolism
chemical_list: D005227:Fatty Acids; D010168:Palmitates; D011522:Protons; D002258:Carbonyl Cyanide m-Chlorophenyl Hydrazone