The effect of pH on the characteristics of the binding of nicotinamide-adenine dinucleotide by nicotinamide-adenine dinucleotide-specific isocitrate dehydrogenase from pea mitochondria.
1. The effect of pH on the V(max.) and concentration of NAD(+) at half-maximum velocity at a constant isocitrate concentration was examined, and the results were related to the requirements for binding of H(+) ions to the enzyme. 2. The effect of varying the NAD(+) concentration on the pH optimum with constant isocitrate concentration was studied. 3. A comparison has been made between the effect of isocitrate concentration on the characteristics of binding of NAD(+) and the effect of NAD(+) concentration on the characteristics of isocitrate binding at three different pH values. 4. The mechanistic and metabolic significance of these studies is considered.
D006863:Hydrogen-Ion Concentration; D007521:Isocitrate Dehydrogenase / Q000378:metabolism*; D008928:Mitochondria / Q000378:metabolism*; D009243:NAD / Q000378:metabolism*; D010944:Plants / Q000378:metabolism; D011485:Protein Binding
D009243:NAD; D007521:Isocitrate Dehydrogenase