Sulfuric Acid Manufacture (Fairlie, Andrew M.)

Effect of dicarboxylic acids on inactivation of chicken liver pyruvate carboxylase caused by incubation at 2° C

“…Addition of Type I inhibitors, e.g. oxalate, fluoropyruvate, has been found to cause marked narrowing of the individual resonance lines in the Mn(II)-EPR spectrum [2] whereas the width of these lines is unaffected or somewhat broadened in the presence of malonate or L-malate [8]. Thus the tightening of the enzyme conformation observed on addition of Type I inhibitors, which is indicated by the decreased rate of inactivation at 2°C ( fig.…”

“…2), is also expressed as a decrease in the extent of interaction of solvent protons with the coordination-sphere of the bound Mn-(II) (cf. [2]).…”

“…Previous studies have shown that various analogs of pyruvate and oxaloacetate act as specific inhibitors of the transcarboxylation partial reaction catalyzed by chicken liver pyruvate carboxylase and, as indicated by the reduction in 1/Tlp* of water protons on formation of the enzyme-ihaibitor complexes. bind to this pyruvate carboxylase in the vicinity of the bound Mn (II) [1,2]. Such binding is accompanied by a marked decrease in the Mn (II)-water proton dipolar interaction [1].…”