scholarly journals Carbon Flux via the Pentose Phosphate Pathway Regulates the Hepatic Expression of the Glucose-6-phosphatase and Phosphoenolpyruvate Carboxykinase Genes in Conscious Rats

1998 ◽  
Vol 273 (1) ◽  
pp. 228-234 ◽  
Author(s):  
Duna Massillon ◽  
Wei Chen ◽  
Nir Barzilai ◽  
Dina Prus-Wertheimer ◽  
Meredith Hawkins ◽  
...  
Keyword(s):  
Pentose Phosphate Pathway ◽  
Carbon Flux ◽  
Phosphoenolpyruvate Carboxykinase ◽  
Pentose Phosphate ◽  
Conscious Rats ◽  
Hepatic Expression

Automatic Redirection of Carbon Flux between Glycolysis and Pentose Phosphate Pathway Using an Oxygen-Responsive Metabolic Switch in Corynebacterium glutamicum

2020 ◽  
Vol 9 (4) ◽  
pp. 814-826
Author(s):  
Shunsuke Kobayashi ◽  
Hideo Kawaguchi ◽  
Tomokazu Shirai ◽  
Kazuaki Ninomiya ◽  
Kenji Takahashi ◽  
...  
Keyword(s):  
Corynebacterium Glutamicum ◽  
Pentose Phosphate Pathway ◽  
Carbon Flux ◽  
Pentose Phosphate ◽  
Metabolic Switch

Optimal Ratio of Carbon Flux between Glycolysis and the Pentose Phosphate Pathway for Amino Acid Accumulation in Corynebacterium glutamicum

2020 ◽  
Vol 9 (7) ◽  
pp. 1615-1622
Author(s):  
Katsuki Murai ◽  
Daisuke Sasaki ◽  
Shunsuke Kobayashi ◽  
Akira Yamaguchi ◽  
Hiroto Uchikura ◽  
...  
Keyword(s):  
Amino Acid ◽  
Corynebacterium Glutamicum ◽  
Pentose Phosphate Pathway ◽  
Carbon Flux ◽  
Pentose Phosphate ◽  
Optimal Ratio ◽  
Acid Accumulation ◽  
Amino Acid Accumulation

Glucose metabolism in Trypanosoma cruzi

2011 ◽  
Vol 51 ◽  
pp. 15-30 ◽  
Author(s):  
Dante A. Maugeri ◽  
Joaquin J.B. Cannata ◽  
Juan-José Cazzulo
Keyword(s):  
Life Cycle ◽  
Glucose Metabolism ◽  
Trypanosoma Cruzi ◽  
Pentose Phosphate Pathway ◽  
Phosphoenolpyruvate Carboxykinase ◽  
Pentose Phosphate ◽  
Pasteur Effect ◽  
Fructose 1,6 Bisphosphatase ◽  
Reduced Products ◽  
Regulatory Controls

The causative agent of Chagas disease, Trypanosoma cruzi, metabolizes glucose through two major pathways: glycolysis and the pentose phosphate pathway. Glucose is taken up via one facilitated transporter and its catabolism by the glycolytic pathway leads to the excretion of reduced products, succinate and l-alanine, even in the presence of oxygen; the first six enzymes are located in a peroxisome-like organelle, the glycosome, and the lack of regulatory controls in hexokinase and phosphofructokinase results in the lack of the Pasteur effect. All of the enzymes of the pentose phosphate pathway are present in the four major stages of the parasite's life cycle, and some of them are possible targets for chemotherapy. The gluconeogenic enzymes phosphoenolpyruvate carboxykinase and fructose-1,6-bisphosphatase are present, but there is no reserve polysaccharide.

scholarly journals Enhanced Endogenous Amino Acids and Energy Metabolism Level for cAMP Biosynthesis by Arthrobacter sp. CCTCC 2013431 with Citrate as Cosubstrate

2021 ◽  
Author(s):  
Zhigang Li ◽  
Baofeng Chen ◽  
Yang Gu ◽  
Hai Tan ◽  
Zhonghua Zhang ◽  
...  
Keyword(s):  
Amino Acids ◽  
Energy Metabolism ◽  
Pentose Phosphate Pathway ◽  
Carbon Flux ◽  
Pentose Phosphate ◽  
Regulation Mechanism ◽  
Feedback Suppression ◽  
Metabolic Intensity ◽  
Glutamate Synthesis ◽  
Tricarboxylate Cycle

Abstract Objectives In our previous study, citrate was used as auxiliary energy substance for improving cAMP fermentation performance, however, the regulation mechanism of citrate on improved cAMP contents was not clear. To elucidate the regulation mechanism, cAMP fermentations with/without citrate addition were conducted in a 7 L fermentor using Arthrobacter sp. CCTCC 2013431 and assays on key enzymes activities, energy metabolism level, amino acids contents and peroxidation level were performed. Results With 3 g/L-broth sodium citrate added, cAMP concentration and conversion yield from glucose reached 4.34 g/L and 0.076 g/g which were improved by 30.7% and 29.8%, respectively, when compared with those of control. Citrate changed carbon flux distribution among different routes and more carbon flux was directed into pentose phosphate pathway beneficial to cAMP synthesis. Meanwhile, energy metabolism together with precursor amino acids levels were improved significantly owing to strengthened metabolic intensity of tricarboxylate cycle by exogenous citrate utilization which provided energy and substance basis for cAMP production. Moreover, higher glutamate synthesis and oxidative stress caused by citrate addition consumed excessive NADPH derived from pentose phosphate pathway by which feedback suppression for pentose phosphate pathway was relieved efficiently.Conclusion Citrate promoted cAMP fermentation production by Arthrobacter sp. CCTCC2013431 due to enhanced precursor amino acids, energy metabolism level and relieved feedback suppression for pentose phosphate pathway.

scholarly journals Systematic Identification of Regulators of Oxidative Stress Reveals Non-canonical Roles for Peroxisomal Import and the Pentose Phosphate Pathway

Cell Reports ◽  
2020 ◽  
Vol 30 (5) ◽  
pp. 1417-1433.e7 ◽  
Author(s):  
Michael M. Dubreuil ◽  
David W. Morgens ◽  
Kanji Okumoto ◽  
Masanori Honsho ◽  
Kévin Contrepois ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Pentose Phosphate Pathway ◽  
Pentose Phosphate ◽  
Systematic Identification

scholarly journals Geranylgeranylacetone attenuates cerebral ischemia–reperfusion injury in rats through the augmentation of HSP 27 phosphorylation: a preliminary study

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Kazuya Matsuo ◽  
Kohkichi Hosoda ◽  
Jun Tanaka ◽  
Yusuke Yamamoto ◽  
Taichiro Imahori ◽  
...  
Keyword(s):  
Cerebral Ischemia ◽  
Reperfusion Injury ◽  
Pentose Phosphate Pathway ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Pentose Phosphate ◽  
Cerebral Ischemia Reperfusion ◽  
Hsp27 Phosphorylation ◽  
Cerebral Ischemia Reperfusion Injury ◽  
Preliminary Study

Abstract Background We previously reported that heat shock protein 27 (HSP27) phosphorylation plays an important role in the activation of glucose-6-phosphate dehydrogenase (G6PD), resulting in the upregulation of the pentose phosphate pathway and antioxidant effects against cerebral ischemia–reperfusion injury. The present study investigated the effect of geranylgeranylacetone, an inducer of HSP27, on ischemia–reperfusion injury in male rats as a preliminary study to see if further research of the effects of geranylgeranylacetone on the ischemic stroke was warranted. Methods In all experiments, male Wistar rats were used. First, we conducted pathway activity profiling based on a gas chromatography–mass spectrometry to identify ischemia–reperfusion-related metabolic pathways. Next, we investigated the effects of geranylgeranylacetone on the pentose phosphate pathway and ischemia–reperfusion injury by real-time polymerase chain reaction (RT-PCR), immunoblotting, and G6PD activity, protein carbonylation and infarct volume analysis. Geranylgeranylacetone or vehicle was injected intracerebroventricularly 3 h prior to middle cerebral artery occlusion or sham operation. Results Pathway activity profiling demonstrated that changes in the metabolic state depended on reperfusion time and that the pentose phosphate pathway and taurine-hypotaurine metabolism pathway were the most strongly related to reperfusion among 137 metabolic pathways. RT-PCR demonstrated that geranylgeranylacetone did not significantly affect the increase in HSP27 transcript levels after ischemia–reperfusion. Immunoblotting showed that geranylgeranylacetone did not significantly affect the elevation of HSP27 protein levels. However, geranylgeranylacetone significantly increase the elevation of phosphorylation of HSP27 after ischemia–reperfusion. In addition, geranylgeranylacetone significantly affected the increase in G6PD activity, and reduced the increase in protein carbonylation after ischemia–reperfusion. Accordingly, geranylgeranylacetone significantly reduced the infarct size (median 31.3% vs 19.9%, p = 0.0013). Conclusions As a preliminary study, these findings suggest that geranylgeranylacetone may be a promising agent for the treatment of ischemic stroke and would be worthy of further study. Further studies are required to clearly delineate the mechanism of geranylgeranylacetone-induced HSP27 phosphorylation in antioxidant effects, which may guide the development of new approaches for minimizing the impact of cerebral ischemia–reperfusion injury.

scholarly journals Pentose Phosphate Pathway Reactions in Photosynthesizing Cells

Cells ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1547
Author(s):  
Thomas D. Sharkey
Keyword(s):  
Pentose Phosphate Pathway ◽  
Strong Association ◽  
Pentose Phosphate ◽  
Critical Component ◽  
Reaction Sequence ◽  
Response To Stress ◽  
Labeling Pattern

The pentose phosphate pathway (PPP) is divided into an oxidative branch that makes pentose phosphates and a non-oxidative branch that consumes pentose phosphates, though the non-oxidative branch is considered reversible. A modified version of the non-oxidative branch is a critical component of the Calvin–Benson cycle that converts CO2 into sugar. The reaction sequence in the Calvin–Benson cycle is from triose phosphates to pentose phosphates, the opposite of the typical direction of the non-oxidative PPP. The photosynthetic direction is favored by replacing the transaldolase step of the normal non-oxidative PPP with a second aldolase reaction plus sedoheptulose-1,7-bisphosphatase. This can be considered an anabolic version of the non-oxidative PPP and is found in a few situations other than photosynthesis. In addition to the strong association of the non-oxidative PPP with photosynthesis metabolism, there is recent evidence that the oxidative PPP reactions are also important in photosynthesizing cells. These reactions can form a shunt around the non-oxidative PPP section of the Calvin–Benson cycle, consuming three ATP per glucose 6-phosphate consumed. A constitutive operation of this shunt occurs in the cytosol and gives rise to an unusual labeling pattern of photosynthetic metabolites while an inducible shunt in the stroma may occur in response to stress.

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