DI- AND TRIPHOSPHOPYRIDINE NUCLEOTIDE ISOCITRIC DEHYDROGENASES IN YEAST

Di- and triphosphopyridine nucleotide isocitric dehydrogenases in yeast.

The biological conversion of d-isocitric to a-ketoglutaric acid was established by the work of Martius and others (1-4). Adler et al. showed that, with extracts of acetone powders of animal tissues, triphosphopyridine nucleotide (TPN) is a specific coenzyme in the reaction and cited evidence for a similar specificity in yeast. Ochoa (5) synthesized oxalosuccinic acid, the intermediate postulate...

Triphosphopyridine nucleotide linked isocitric dehydrogenase in bacteria.

The conversion of isocitric acid to alpha-ketoglutarate has been demonstrated both in animal tissues (Martius, 1937; Krebs and Johnson, 1937; Adler et al., 1939; Ochoa, 1948) and in yeast (Kornberg and Pricer, 1951; Foulkes, 1951). Triphosphopyridine nucleotide was first implicated as a specific coenzyme for this reaction by Adler et al. (1939). Recently Kornberg and Pricer (1951) found in yeas...

Effects of cold acclimatization on liver di- and triphosphopyridine nucleotide.

The levels of oxidized and reduced diand triphosphopyridine nucleotide were measured in liver tissue from rats that had been exposed to cold (40 ± 1° C) for one month. These animals exhibited about 65% more TPNH and total triphosphopyridine nucleotide than control animals maintained at an ambient temperature of 250 ± 10 C. The significance of these alterations to the efficiency of oxidative pho...

The measurement of triphosphopyridine nucleotide and reduced triphosphopyridine nucleotide and the role of hemoglobin in producing erroneous triphosphopyridine nucleotide values.

A method is described for determining TPN+ and TPNH in a single tissue homogenate made in dilute NaOH at 0’. One portion, for TPN+, is acidified after adding ascorbic acid to prevent TPNH oxidation. A second portion, for TPNH, is heated (still alkaline) after adding cysteine to prevent oxidation. If desired, a third portion can be analyzed directly without heating for total TPN (TPN+ plus TPNH)...

Preparation of triphosphopyridine nucleotide.