On the regulatory properties of the pyruvate kinase from Trypanosoma cruzi epimastigotes
TLDR
The pyruvate kinase from Trypanosoma cruzi epimastigotes was activated by fructose 2,6-diphosphate through a decrease in (S) 0.5 and an increase in Vmax for both substrates, suggesting that the effects are allosteric, and not due to chelation.Abstract:
The pyruvate kinase from Trypanosoma cruzi epimastigotes was activated by fructose 2,6-diphosphate ((A) 0.5 = 0.17 μM), through a decrease in (S) 0.5 and an increase in Vmax for both substrates. The enzyme was 50% inhibited by 0.9 mM ATP or 0.5 mM Pi in the presence of 30 mM MgC12; these inhibitions were completely counteracted by 1.5 μM fructose 2,6-diphosphate. Both facts suggest that the effects are allosteric, and not due to chelation.read more
Citations
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Aerobic fermentation of glucose by trypanosomatids.
TL;DR: The consumption of glucose by trypanosomatid protozoa is characterized by the excretion of reduced products such as succinate, pyruvate, ethanol, l‐alanine, or lactate not only in anaerobiosis, but also under aerobic conditions.
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Succinate Secreted by Trypanosoma brucei Is Produced by a Novel and Unique Glycosomal Enzyme, NADH-dependent Fumarate Reductase
Sébastien Besteiro,Marc Biran,Nicolas Biteau,Virginie Coustou,Théo Baltz,Paul Canioni,Frédéric Bringaud +6 more
TL;DR: It is concluded that FRDg plays a key role in the energy metabolism by participating in the maintenance of the glycosomal NAD+/NADH balance and proposes a revised model of glucose metabolism in procyclic trypanosomes that may also be valid for all othertrypanosomatids except the T. brucei bloodstream form.
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Intermediate metabolism in Trypanosoma cruzi.
TL;DR: Among the enzymes of amino acid catabolism, two glutamate dehydrogenases (one NADP- and the other NAD-linked), alanine aminotransferase, and the major enzymes of aromatic amino acidCatabolism (tyrosine isinotranferase and aromatic α-hydroxy acid dehydrogenase), have been characterized and proposed to be involved in the reoxidation of glycolytic NADH.
Journal ArticleDOI
The pentose phosphate pathway in Trypanosoma cruzi.
TL;DR: Subcellular localisation experiments suggested that the PPP enzymes have a cytosolic component, predominant in most cases, although all of them also seem to have organellar localisation(s).
Journal ArticleDOI
Intermediary metabolism of Trypanosoma cruzi
TL;DR: The characteristics o f the intermediary metabolism of Trypanosoma cruzi (the causative agent of Chagas disease), which are responsible for the unusual capacity of this parasite to use carbohydrates or amino acids as carbon and energy sources without drastic changes in its catabolic enzyme levels are discussed.
References
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Journal Article
Protein Measurement with the Folin Phenol Reagent
TL;DR: Procedures are described for measuring protein in solution or after precipitation with acids or other agents, and for the determination of as little as 0.2 gamma of protein.
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The determination of inorganic phosphate in the presence of labile phosphate esters.
Oliver H. Lowry,Jeanne A. Lopez +1 more
TL;DR: It has been found possible to establish conditions under which inorganic phosphate can readily be determined in the presence of labile esters.
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A kinetic study of pyrophosphate: fructose-6-phosphate phosphotransferase from potato tubers. Application to a microassay of fructose 2,6-bisphosphate.
TL;DR: A procedure allowing one to measure fructose 2,6-bisphosphate in amounts lower than a picomole, is described and the kinetic properties of the purified enzyme have been investigated.
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End products and enzyme levels of aerobic glucose fermentation in trypanosomatids.
TL;DR: The results are in good agreement with current ideas on the mechanism of aerobic glucose fermentation by trypanosomatids, and suggest that, under the experimental conditions used, both T. cruzi and C. fasciculata used glucose perferentially over amino acids for growth.