title: Nonspecific inhibition of dehydrogenases by folates: an artifact.
abstract: The previous reports of inhibition of alcohol dehydrogenase and lactate dehydrogenase by the vitamin folic acid and its analogues are in error. The high absorbance of solutions containing folate causes distortion of the measurements of reaction velocities, leading to apparent inhibitions. When cuvettes of sufficiently short optical path length are used, no inhibition by folate can be observed. Similarly, the reported inhibition of ribonuclease by folate is an artifact. Glutamate dehydrogenase and dihydropterin reductase actually are inhibited by folate. The reported nonspecific inhibitions of over a dozen enzymes by folate, though, must be regarded as erroneous.
mesh_terms: D000429:Alcohol Oxidoreductases / Q000037:antagonists & inhibitors*; D000818:Animals; D002417:Cattle; D004093:Dihydropteridine Reductase / Q000037:antagonists & inhibitors; D005492:Folic Acid / Q000494:pharmacology*; D005969:Glutamate Dehydrogenase / Q000037:antagonists & inhibitors; D006736:Horses; D007668:Kidney / Q000201:enzymology; D007700:Kinetics; D007770:L-Lactate Dehydrogenase / Q000037:antagonists & inhibitors; D008099:Liver / Q000201:enzymology; D009206:Myocardium / Q000201:enzymology; D010088:Oxidoreductases / Q000037:antagonists & inhibitors*; D012260:Ribonucleases / Q000037:antagonists & inhibitors
chemical_list: D005492:Folic Acid; D010088:Oxidoreductases; D000429:Alcohol Oxidoreductases; D007770:L-Lactate Dehydrogenase; D005969:Glutamate Dehydrogenase; D004093:Dihydropteridine Reductase; D012260:Ribonucleases