title: Fasciola hepatica: inhibition of phosphoenolpyruvate carboxykinase, and end-product formation by quinolinic acid and 3-mercaptopicolinic acid.
abstract: Quinolinic acid and 3-mercaptopicolinic acid act as inhibitors of Fasciola hepatica phosphoenolpyruvate carboxykinase. Low concentrations of these compounds (0.1 mM quinolinate and 0.01 mM 3-mercaptopicolinate) resulted in noncompetitive inhibition, which became mixed inhibition at higher concentrations (1.5 and 0.15 mM, respectively). 3-mercaptopicolinic acid proved to be a much more potent effector than quinolinic acid. Both quinolinic acid and 3-mercaptopicolinic acid caused a significant reduction in the total amount of end product excreted, again 3-mercaptopicolinate being more effective than quinolinate. When glucose was present in the medium, both propionate and acetate levels fell significantly with both inhibitors; however, only 3-mercaptopicolinic acid caused an effect in the absence of glucose.
mesh_terms: D000085:Acetates / Q000378:metabolism; D000818:Animals; D004305:Dose-Response Relationship, Drug; D005210:Fasciola hepatica / Q000187:drug effects / Q000201:enzymology*; D007773:Lactates / Q000378:metabolism; D019344:Lactic Acid; D010729:Phosphoenolpyruvate Carboxykinase (GTP) / Q000037:antagonists & inhibitors*; D010848:Picolinic Acids / Q000494:pharmacology*; D011422:Propionates / Q000378:metabolism; D011725:Pyridines / Q000494:pharmacology*; D011770:Pyruvate Kinase / Q000037:antagonists & inhibitors; D017378:Quinolinic Acid; D011805:Quinolinic Acids / Q000494:pharmacology*; D013386:Succinates / Q000378:metabolism; D019802:Succinic Acid; D014364:Tryptophan / Q000494:pharmacology
chemical_list: D000085:Acetates; D007773:Lactates; D010848:Picolinic Acids; D011422:Propionates; D011725:Pyridines; D011805:Quinolinic Acids; D013386:Succinates; D019344:Lactic Acid; C008363:3-mercaptopicolinic acid; D014364:Tryptophan; D019802:Succinic Acid; D011770:Pyruvate Kinase; D010729:Phosphoenolpyruvate Carboxykinase (GTP); D017378:Quinolinic Acid