The role of citrate on the oxidative metabolism of submerged cultures of Claviceps purpurea 129

1981 ◽  
Vol 129 (3) ◽  
pp. 251-253 ◽  
Author(s):  
Sylvie Pazoutová ◽  
Zdeněk Řeháček
Keyword(s):  
Oxidative Metabolism ◽  
Claviceps Purpurea ◽  
Submerged Cultures

HIF-1α in endurance training: suppression of oxidative metabolism

2007 ◽  
Vol 293 (5) ◽  
pp. R2059-R2069 ◽  
Author(s):  
Steven D. Mason ◽  
Helene Rundqvist ◽  
Ioanna Papandreou ◽  
Roger Duh ◽  
Wayne J. McNulty ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Endurance Training ◽  
Oxidative Metabolism ◽  
Hypoxia Inducible Factor ◽  
Transcriptional Response ◽  
Oxidative Capacity ◽  
Pyruvate Dehydrogenase Kinase ◽  
Amp Activated Protein Kinase ◽  
Training Protocol

During endurance training, exercising skeletal muscle experiences severe and repetitive oxygen stress. The primary transcriptional response factor for acclimation to hypoxic stress is hypoxia-inducible factor-1α (HIF-1α), which upregulates glycolysis and angiogenesis in response to low levels of tissue oxygenation. To examine the role of HIF-1α in endurance training, we have created mice specifically lacking skeletal muscle HIF-1α and subjected them to an endurance training protocol. We found that only wild-type mice improve their oxidative capacity, as measured by the respiratory exchange ratio; surprisingly, we found that HIF-1α null mice have already upregulated this parameter without training. Furthermore, untrained HIF-1α null mice have an increased capillary to fiber ratio and elevated oxidative enzyme activities. These changes correlate with constitutively activated AMP-activated protein kinase in the HIF-1α null muscles. Additionally, HIF-1α null muscles have decreased expression of pyruvate dehydrogenase kinase I, a HIF-1α target that inhibits oxidative metabolism. These data demonstrate that removal of HIF-1α causes an adaptive response in skeletal muscle akin to endurance training and provides evidence for the suppression of mitochondrial biogenesis by HIF-1α in normal tissue.

scholarly journals Oxidative Metabolism of BDE-99 by Human Liver Microsomes: Predominant Role of CYP2B6

2012 ◽  
Vol 129 (2) ◽  
pp. 280-292 ◽  
Author(s):  
Claudio A. Erratico ◽  
András Szeitz ◽  
Stelvio M. Bandiera
Keyword(s):  
Oxidative Metabolism ◽  
Human Liver ◽  
Liver Microsomes ◽  
Human Liver Microsomes ◽  
Predominant Role

Further evaluation of luminol-enhanced luminescence in the diagnosis of disorders of leukocyte oxidative metabolism: role of myeloperoxidase.

1983 ◽  
Vol 29 (3) ◽  
pp. 513-515 ◽  
Author(s):  
M S Cohen ◽  
P S Shirley ◽  
L R DeChatelet
Keyword(s):  
Chronic Granulomatous Disease ◽  
Oxidative Metabolism ◽  
Clinical Consequence ◽  
Granulomatous Disease ◽  
Myeloperoxidase Deficiency ◽  
Luminescence Assay ◽  
Diagnostic Confusion ◽  
Enhanced Luminescence ◽  
Hereditary Nature

Abstract Chemiluminescence can be used to identify defects in the oxidative metabolism of granulocytes. This procedure has recently been adopted for use with microliter quantities of whole blood, appropriate for prenatal or neonatal study. Although the contribution of myeloperoxidase to the chemiluminescence assay has been noted, the possible diagnostic confusion between chronic granulomatous disease of childhood (which is rare and severe) and myeloperoxidase deficiency (which is common and of little clinical consequence) has not been stressed. We report a father and his infant daughter whose cells emitted no light in the luminol-enhanced luminescence assay; both patients are totally peroxidase deficient. These results emphasize the hereditary nature of myeloperoxidase deficiency, and the possibility for erroneous diagnosis of chronic granulomatous disease of childhood based on the luminol-enhanced luminescence test.

scholarly journals Pathogenesis of alcoholic liver disease: Role of oxidative metabolism

2014 ◽  
Vol 20 (47) ◽  
pp. 17756-17772 ◽  
Author(s):  
Elisabetta Ceni ◽  
Tommaso Mello ◽  
Andrea Galli
Keyword(s):  
Liver Disease ◽  
Alcoholic Liver Disease ◽  
Oxidative Metabolism

scholarly journals Role of convective O2 delivery in determiningV˙o 2 on-kinetics in canine muscle contracting at peak V˙o 2

2000 ◽  
Vol 89 (4) ◽  
pp. 1293-1301 ◽  
Author(s):  
Bruno Grassi ◽  
Michael C. Hogan ◽  
Kevin M. Kelley ◽  
William G. Aschenbach ◽  
Jason J. Hamann ◽  
...  
Keyword(s):  
Blood Flow ◽  
Steady State ◽  
Muscle Fatigue ◽  
Oxidative Metabolism ◽  
Muscle Blood Flow ◽  
Content Difference ◽  
O2 Delivery ◽  
Gastrocnemius Muscles

A previous study (Grassi B, Gladden LB, Samaja M, Stary CM, and Hogan MC, J Appl Physiol 85: 1394–1403, 1998) showed that convective O2 delivery to muscle did not limit O2 uptake (V˙o 2) on-kinetics during transitions from rest to contractions at ∼60% of peakV˙o 2. The present study aimed to determine whether this finding is also true for transitions involving contractions of higher metabolic intensities.V˙o 2 on-kinetics were determined in isolated canine gastrocnemius muscles in situ ( n = 5) during transitions from rest to 4 min of electrically stimulated isometric tetanic contractions corresponding to the muscle peakV˙o 2. Two conditions were compared: 1) spontaneous adjustment of muscle blood flow (Q˙) (Control) and 2) pump-perfused Q˙, adjusted ∼15–30 s before contractions at a constant level corresponding to the steady-state value during contractions in Control (Fast O2 Delivery). In Fast O2 Delivery, adenosine was infused intra-arterially. Q˙ was measured continuously in the popliteal vein; arterial and popliteal venous O2 contents were measured at rest and at 5- to 7-s intervals during the transition. Muscle V˙o 2 was determined as Q˙times the arteriovenous blood O2 content difference. The time to reach 63% of the V˙o 2 difference between resting baseline and steady-state values during contractions was 24.9 ± 1.6 (SE) s in Control and 18.5 ± 1.8 s in Fast O2 Delivery ( P < 0.05). FasterV˙o 2 on-kinetics in Fast O2Delivery was associated with an ∼30% reduction in the calculated O2 deficit and with less muscle fatigue. During transitions involving contractions at peak V˙o 2, convective O2 delivery to muscle, together with an inertia of oxidative metabolism, contributes in determining theV˙o 2 on-kinetics.

scholarly journals Susceptibility Level of the Colorado Potato Beetle (Leptinotarsa Decemlineata Say) to Chlorpyrifos and Acetamiprid in Poland and Resistance Mechanisms of the Pest to Chlorpyrifos

2011 ◽  
Vol 51 (3) ◽  
pp. 279-284 ◽  
Author(s):  
Paweł Węgorek ◽  
Joanna Zamojska ◽  
Marek Mrówczyński
Keyword(s):  
Colorado Potato Beetle ◽  
Oxidative Metabolism ◽  
Leptinotarsa Decemlineata ◽  
Essential Role ◽  
Resistance Mechanisms ◽  
Glutathione Transferases ◽  
Main Role ◽  
Potato Beetle ◽  
Leptinotarsa Decemlineata Say

Susceptibility Level of the Colorado Potato Beetle (Leptinotarsa DecemlineataSay) to Chlorpyrifos and Acetamiprid in Poland and Resistance Mechanisms of the Pest to ChlorpyrifosNowadays, neonicotinoids play an essential role in the control of the Colorado potato beetle (CPB) in Poland. Taking into consideration that CPB shows some resistance to pyrethroids and the main role of oxidative metabolism in this resistance, research was conducted to estimate CPB susceptibility level to chlorpyrifos and acetamiprid. The results pointed to a lack of CPB resistance to acetamiprid and a weak susceptibility level to chlorpyrifos by the CPB. For this reason, the second part of the experiment was aimed at detecting the resistance mechanisms of the CPB to chlorpyrifos. Results showed that none of the tested enzyme groups (oxidases, esterases and glutathione transferases) are the reason for CPB resistance to chlorpyrifos. The experiments revealed an increase in the beetles survival after adding oxidative enzyme blocker to chlorpyrifos.

scholarly journals The metabolism of nitrilotriacetate by a pseudomonad

1973 ◽  
Vol 136 (4) ◽  
pp. 1059-1068 ◽  
Author(s):  
Roger E. Cripps ◽  
Ann S. Noble
Keyword(s):  
Oxidative Metabolism ◽  
Sole Source ◽  
Serine Hydroxymethyltransferase ◽  
Glycine Decarboxylase ◽  
Hydroxypyruvate Reductase ◽  
Anaerobic Conversion ◽  
Thiamin Pyrophosphate ◽  
Serine Metabolism ◽  
Successive Removal

1. An organism that grows on nitrilotriacetate as sole source of carbon and energy was isolated in pure culture and was identified as a pseudomonad. 2. Cell-free extracts of the nitrilotriacetate-grown pseudomonad contain an enzyme that catalyses the NADH-and O2-dependent oxidation of nitrilotriacetate to iminodiacetate and glyoxalate. This enzyme is absent from extracts of glucose-grown cells. 3. Compared with growth on glucose, growth on nitrilotriacetate results in increased activities of enzymes of glycine and serine metabolism, namely serine hydroxymethyltransferase, glycine decarboxylase, serine–oxaloacetate aminotransferase and hydroxypyruvate reductase. 4. Cell-free extracts of the nitrilotriacetate-grown organism contain the enzyme glyoxalate carboligase and, when supplemented with NADH, Mg2+and thiamin pyrophosphate, can catalyse the anaerobic conversion of glyoxalate into glycerate. 5. These results are incorporated in a scheme which shows the oxidative metabolism of nitrilotriacetate by the successive removal of C2 units to form 2mol of glyoxalate and 1mol of glycine per mol of nitrilotriacetate degraded. The glyoxalate and glycine are then both metabolized to glycerate by separate pathways, via tartronic semialdehyde and serine respectively. The role of this scheme in the growth of the organism on nitrilotriacetate is discussed.

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