title: Conformations of diphosphopyridine coenzymes upon binding to dehydrogenases.
abstract: The binding of oxidized as well as reduced coenzyme to some dehydrogenases has been studied under different concentration ratios and temperatures by nuclear magnetic resonance spectroscopy. A significant difference in the spectral behavior between DPN(+) and DPNH upon binding is interpreted in terms of fast and slow on-off rates relative to the nuclear magnetic resonance time scale in the binding of these two coenzymes. Significant downfield shifts of DPN(+) were observed upon binding, comparable in magnitude to those expected upon opening (destacking) of the coenzymes in the case of chicken-muscle and lobster-tail lactate dehydrogenase (EC 1.1.1.27) and yeast alchol dehydrogenase (EC 1.1.1.1.). A preliminary survey of several other dehydrogenases is consistent with these findings. In the case of 3-phosphoglyceraldehyde dehydrogenase, there is a possibility that the coenzyme exists in the folded form.
mesh_terms: D000429:Alcohol Oxidoreductases / Q000032:analysis*; D000818:Animals; D001665:Binding Sites; D002645:Chickens; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases / Q000032:analysis; D005993:Glycerolphosphate Dehydrogenase / Q000032:analysis; D006736:Horses; D007527:Isoenzymes; D007700:Kinetics; D007770:L-Lactate Dehydrogenase / Q000032:analysis; D008099:Liver / Q000201:enzymology; D009682:Magnetic Resonance Spectroscopy; D008291:Malate Dehydrogenase / Q000032:analysis; D008968:Molecular Conformation; D009132:Muscles / Q000201:enzymology; D009206:Myocardium / Q000201:enzymology; D009243:NAD / Q000032:analysis*; D008121:Nephropidae; D010084:Oxidation-Reduction; D011817:Rabbits; D013696:Temperature; D015003:Yeasts / Q000201:enzymology
chemical_list: D007527:Isoenzymes; D009243:NAD; D000429:Alcohol Oxidoreductases; D005993:Glycerolphosphate Dehydrogenase; D007770:L-Lactate Dehydrogenase; D008291:Malate Dehydrogenase; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases