A sensitive method for estimation of oxaloacetate

Kalnitsky, George; Tapley, Donald F.

doi:10.1042/bj0700028

Cited by 68 publications

(14 citation statements)

References 18 publications

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“…Protein was determined with the micro-biuret procedure (3). ,B-Keto acids were detected using the p-nitroaniline diazo reagent (19).…”

Section: Lism By B Abortus 621mentioning

confidence: 99%

Erythritol catabolism by Brucella abortus

Sperry¹,

Robertson²

1975

J Bacteriol

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Cell extracts of Brucella abortus (British 19) catabolized erythritol through a series of phosphorylated intermediates to dihydroxyacetonephosphate and CO2. Cell extracts required adenosine 5'-triphosphate (ATP), nicotinamide adenine dinucleotide (NAD), Mg2+, inorganic orthophosphate, and reduced glutathione for activity. The first reaction in the pathway was the phosphorylation of mesoerythritol with an ATP-dependent kinase which formed D-erythritol 1-phosphate (D-erythro-tetritol 1-phosphate). D-Erythritol 1-phosphate was oxidized by an NAD-dependent dehydrogenase to D-erythrulose 1-phosphate (D-glycero-2tetrulose 1-phosphate). B. abortus was found to lack the succeeding enzyme in the pathway and was used to prepare substrate amounts of D-erythrulose 1-phosphate. D-Erythritol 1-phosphate dehydrogenase (D-erythro-tetritol 1-phosphate: NAD 2-oxidoreductase) is probably membrane bound. D-Erythrulose 1-phosphate was oxidized by an NAD-dependent dehydrogenase to 3-keto-Lerythrose 4-phosphate (L-glycero-3-tetrosulose 4-phosphate) which was further oxidized at C-1 by a membrane-bound dehydrogenase coupled to the electron transport system. Either oxygen or nitrate had to be present as a terminal electron acceptor for the oxidation of 3-keto-L-erythrose 4-phosphate to 3-keto-L-erythronate 4-phosphate (L-glycero-3-tetrulosonic acid 4-phosphate). The ,Bketo acid was decarboxylated by a soluble decarboxylase to dihydroxyacetonephosphate and CO2. Dihydroxyacetonephosphate was converted to pyruvic acid by the final enzymes of glycolysis. The apparent dependence on the electron transport system for erythritol catabolism appears to be unique in Brucella and may play an important role in coupling metabolism to active transport and generation of ATP.Smith and co-workers (20, 33, 37) first described the unique role of erythritol in the pathogenesis and physiology of the genus Brucella. Extensive growth of Brucella occurs in fetal tissues and fluids of pregnant cows, sheep, goats, and sows, leading to endotoxin shock and abortion. In contrast to domestic animals, the bacteria cause a chronic disease in man in which cells of the reticuloendothelial system are parasitized. It is significant that erythritol is present only in fetal fluids and tissues of animals which suffer acute infectious abortions; however, considerable controversy has been raised concerning possible relationship(s) between erythritol utilization and virulence (23,24). Infections with B. melitensis and B. suis have been enhanced by co-injection of erythritol (20). Erythritol may play some selective role in tissue localization, since most maternal pathogens do not localize in fetal tissues. It is possible that, through the centuries of association with domestic animals, a unique enzyme system for erythritol catabolism has evolved which is important in the physiology of Brucella.Anderson and Smith (1) reported that B. abortus preferentially utilized erythritol in a complex medium containing high concentrations of D-glucose and amino acids. The 4-carbon polyol serve...

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“…Protein was determined with the micro-biuret procedure (3). ,B-Keto acids were detected using the p-nitroaniline diazo reagent (19).…”

Section: Lism By B Abortus 621mentioning

confidence: 99%

Erythritol catabolism by Brucella abortus

Sperry¹,

Robertson²

1975

J Bacteriol

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“…As has been pointed out by Pearson (24) and Buckel and Eggerer (25), the coupled assay for acetyl CoA underestimates the concentration of this compound because of a shift in the equilibrium of the malate dehydrogenase reaction during the assay. The actual values obtained in these experiments have been corrected according to the formula of the latter authors (25 Kalnitsky and Tapley (27).…”

Section: In Vivo-in Vitro Experimentsmentioning

confidence: 99%

“…The reaction was allowed to proceed for 30 minutes at room temperature and was then stopped by the addition of 0.25 ml of 4 N HCl. After standing for 8 minutes to destroy any oxalacetate present (27), the solution was extracted with * Experimental details are given in the text. Results for glycogen and fatty acid are given as milligrams per 1,000 mg wet weight of liver and are tabulated as means and standard errors of the means for nine animals at each time interval.…”

Section: In Vivo Experimentsmentioning

confidence: 99%

Studies in the Ketosis of Fasting*

Foster¹

1967

J. Clin. Invest.

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Summary. A series of experiments was performed during the induction of starvation ketosis and in the acute reversal of the ketotic state. In contrast to the predictions of two widely held theories of ketogenesis, control of acetoacetate production by the liver appeared to be unrelated to changes in fatty acid mobilization from the periphery, fatty acid oxidation, fatty acid synthesis, or the acetyl coenzyme A concentration in the liver.Ketosis of fasting was shown to be reversible within 5 minutes by the injection of glucose or insulin. This effect was due to a prompt cessation of acetoacetate production by the liver. The possibility is raised that the ketosis of fasting is due to a direct activation of acetoacetate-synthesizing enzymes secondary to a starvation-induced depression of insulin secretion by the pancreas.

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“…Концентрацию оксалоацетата определяли колориметрическим методом, базирующемся на взаимодействии оксалоацетата с n-нитроанилином с образованием NN¢-бис-(n-нитрофенил)-С-оксалилформазана, имеющим максимум поглощения при l=450 нм [21]. Концентрацию малата определяли энзиматическим методом и регистрировали спектрофотометрически по накоплению NADH, эквимолярного количеству окисленного малата, при l=340 нм [22].…”

Section: методикаunclassified

Activity of liver mitochondrial NAD+-dependent dehydrogenases of the krebs cycle in rats with acetaminophen-induced hepatitis developed under conditions of alimentary protein deficiency

Voloshchuk

Kopylchuk

2016

BIOMED KHIM

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Activity of isocitrate dehydrogenase, a-ketoglutarate dehydrogenase, malate dehydrogenase, and the NAD+/NADН ratio were studied in the liver mitochondrial fraction of rats with toxic hepatitis induced by acetaminophen under conditions of alimentary protein deprivation. Acetaminophen-induced hepatitis was characterized by a decrease of isocitrate dehydrogenase, a-ketoglutarate dehydrogenase and malate dehydrogenase activities, while the mitochondrial NAD+/NADН ratio remained at the control level. Modeling of acetaminophen-induced hepatitis in rats with alimentary protein caused a more pronounced decrease in the activity of NAD+-dependent dehydrogenases studied and a 2.2-fold increase of the mitochondrial NAD+/NADН ratio. This suggests that alimentary protein deprivation potentiated drug-induced liver damage

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A sensitive method for estimation of oxaloacetate

Cited by 68 publications

References 18 publications

Erythritol catabolism by Brucella abortus

Erythritol catabolism by Brucella abortus

Studies in the Ketosis of Fasting*

Activity of liver mitochondrial NAD+-dependent dehydrogenases of the krebs cycle in rats with acetaminophen-induced hepatitis developed under conditions of alimentary protein deficiency

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