Intracellular Distribution of Isocitrate-Nicotinamide-Adenine Dinucleotide Phosphate - Oxidoreductase Activity During Development of the Chick Embryo

Baker, Wilber W.; Newburgh, R.W.

doi:10.1042/bj0890510

Cited by 11 publications

(3 citation statements)

References 8 publications

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“…One of the earliest functions ascribed to wild-type IDH1 was a role in lipid metabolism based on the observation that the enzymatic reaction of IDH1 produces NADPH [19]. IDH1 was discovered as early as 1950 when Hogeboom and Schneider [20] identified isocitrate dehydrogenase activity in the cytoplasm of liver tissue obtained from adult mice.…”

Section: Contents Lists Available At Sciencedirectmentioning

confidence: 99%

“…These investigators noted the increased production of NADPH following the addition of isocitrate to rat liver cytosolic preparations. Early investigators hypothesized that the function of IDH1 may be to provide high levels of NADPH for lipid biosynthesis since NADPH is an obligatory reducing equivalent for the synthesis of fatty acids and lipids [7,19]. It was also hypothesized that IDH1 participates in a biochemical pathway in the rat liver where carbons derived from glutamate become incorporated into fatty acids [11].…”

Section: Contents Lists Available At Sciencedirectmentioning

confidence: 99%

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IDH1, lipid metabolism and cancer: Shedding new light on old ideas

Bogdanovic

2015

Biochimica et Biophysica Acta (BBA) - General Subjects

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Section: Contents Lists Available At Sciencedirectmentioning

confidence: 99%

Section: Contents Lists Available At Sciencedirectmentioning

confidence: 99%

IDH1, lipid metabolism and cancer: Shedding new light on old ideas

Bogdanovic

2015

Biochimica et Biophysica Acta (BBA) - General Subjects

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“…In the chick embryo heart, which begins beating at about the 36th hour of incubation, and which reaches its adult morphological form by the 8th day, the protein and DNA contents become constant at about the 8th day of incubation. However, Baker and Newburgh (7) found that the RNA:DNA ratio decreases continually from the 4th day of incubation to hatching. Consequently, one might expect that the relative importance of the phosphogluconate pathway to the utilization of glucose would be greater in the early embryo than in the older embryo or the adult chick.…”

Section: Introductionmentioning

confidence: 99%

Glucose Utilization by Chick Embryo Heart Homogenates

Coffey

Cheldelin

Newburgh

1964

The Journal of General Physiology

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Homogenates of early chick embryos and homogenates of early chick embryonic hearts utilized the phosphogluconate pathway of glucose catabolism to a greater extent, relative to the glycolytic-Krebs cycle pathway, than did homogenates of hearts from older chick embryos or adult chicks. An abrupt drop in the relative participation by the phosphogluconate pathway in embryo heart homogenates occurs at about 5 to 7 days of incubation. Heart homogenates from adult chicks catabolize glucose almost entirely by the glycolytic-Krebs cycle pathway, with negligible participation by the phosphogluconate pathway.

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Isozymes of isocitrate dehydrogenase: Subunit structure and intracellular location

Henderson

1965

J. Exp. Zool.

172

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Isocitrate dehydrogenase (IDH) exists in mammalian tissues as three enzymes, one specific for NAD and two specific for NADP. The two NADP isozymes differ in electrophoretic mobility, immunological characteristics, and tissue and subcellular location. One is found mainly in the mitochondrial fraction and one in the supernatant fraction of tissue homogenates. Two allelic forms of the supernatant NADP isocitrate dehydrogenase have been described in inbred strains of mice. In a heterozygote containing both alleles, three forms of the supernatant NADP-IDH are generated in a ratio of 1:2:1. This implies that the supernatant enzyme is a dimer. The mitochondrial form is not affected by the gene, indicating separate genetic control. Liver mitochondria contain both the supernatant and the mitochondrial isozymes. Thus at least one protein found in the mitochondria is encoded in a nuclear gene.Research in biochemical genetics led to the formulation of the one-gene-one enzyme hypothesis with the consequent expectation that one enzyme would exist as a single molecular type within an organism. Exceptions would be diploid organisms carrying allelic genes for the enzyme, in which case two forms of the enzyme would be found. However, in recent years an increasing amount of evidence has shown that many enzymes exist in multiple molecular forms, or as isozymes, within the cells of a single organism, even when that organism is homozygous (Markert and Mller, '59; Wieland and Pfleiderer, '57; Vessel1 and Bearn, '58). Such molecular heterogeneity has been detected by many different techniques, including electrophoresis, column chromatography, centrifugation, salt fractionation, and by determination of tissue specific differences in enzyme kinetics, coenzyme specificity, and immunochemical behavior. The moleculuar basis for this heterogeneity may be different for different enzymes. The binding of small molecules to the enzyme can give rise to multiple forms, as in the case of the two active forms of phosphoglucomutase, which differ in the presence of a phosphate group bound to one form during the enzymatic reaction (Koshland, '64 be polymers of different numbers of the same polypeptide subunit. The two forms of phosphorylase, a and b, differ in that one is a dimer of the other as well as in the presence of two phosphate groups bound to serine residues in the dimer (Brown and Cori, '61).On the other hand, the several forms of an enzyme may differ significantly in primary protein structure, and thus be under multiple gene control, as has been clearly shown for the five principal isozymes of lactate dehydrogenase (LDH) . These isozymes are found in characteristic relative amounts in the different tissues of an organism (Markert and MBller, '59) and have the same molecular weight but differ in electrophoretic mobility. The two extreme forms, LDH-1 and LDH-5, differ in amino acid content, immunological specificity, kinetic properties, coenzyme specificity, heat stability, and other characteristics. The intermediate forms, , are also...

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Intracellular Distribution of Isocitrate-Nicotinamide-Adenine Dinucleotide Phosphate - Oxidoreductase Activity During Development of the Chick Embryo

Cited by 11 publications

References 8 publications

IDH1, lipid metabolism and cancer: Shedding new light on old ideas

IDH1, lipid metabolism and cancer: Shedding new light on old ideas

Glucose Utilization by Chick Embryo Heart Homogenates

Isozymes of isocitrate dehydrogenase: Subunit structure and intracellular location

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