title: An investigation of the nicotinamide-adenine dinucleotide-induced 'tightening' of the structure of glyceraldehyde 3-phosphate dehydrogenase.
abstract: An investigation was made of the effect of NAD+ analogues on subunit interactions in yeast and rabbit muscle glyceraldehyde 3-phosphate dehydrogenases by using the subunit exchange (hybridization) method described previously [e.g. see Osborne & Hollaway (1975) Biochem. J. 151, 37-45]. The ligands ATP, ITP, ADP, AMP, cyclic AMP and ADP-ribose like NADH, all caused an apparent weakening of intramolecular subunit interactions, whereas NAD+ caused an apparent increase in the stability of the tetrameric enzyme molecules. A mixture of NMN and AMP, although it did not simulate completely the NAD+-induced 'tightening' of the enzyme structure, did result in a more than 20-fold decrease in the rate of subunit exchange compared with that in the presence of AMP alone. These results show that occupancy of the NMN subsite of the enzyme NAD+-binding site is insufficient in itself to give the marked tightening of the enzyme structure induced by NAD+. The 'tightening' effect is specific in that it seems to require a phosphodiester link between NMN and ADP-ribose. These effects are discussed in terms of the detailed X-ray structure of the lobster holoenzyme [Buehner et al. (1974) J. Mol. Biol. 90, 25-49].
mesh_terms: D000244:Adenosine Diphosphate; D000247:Adenosine Diphosphate Sugars; D000249:Adenosine Monophosphate; D000255:Adenosine Triphosphate; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases; D007292:Inosine Nucleotides; D007700:Kinetics; D008274:Magnesium; D009243:NAD; D009537:Nicotinamide Mononucleotide; D011485:Protein Binding; D011487:Protein Conformation; D012441:Saccharomyces cerevisiae / Q000201:enzymology
chemical_list: D000247:Adenosine Diphosphate Sugars; D007292:Inosine Nucleotides; D009243:NAD; D009537:Nicotinamide Mononucleotide; D000249:Adenosine Monophosphate; D000244:Adenosine Diphosphate; D000255:Adenosine Triphosphate; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases; D008274:Magnesium