Notizen: Isolation and Respiratory Assay of Earthworm Body Wall Mitochondria

1984 ◽  
Vol 39 (7-8) ◽  
pp. 853-855
Author(s):  
T. V. Rao ◽  
U. C. Biswal
Keyword(s):  
Cytochrome C ◽  
Oxidative Phosphorylation ◽  
Succinate Dehydrogenase ◽  
Cytochrome Oxidase ◽  
Body Wall ◽  
Reaction Medium ◽  
Respiratory Metabolism ◽  
Respiratory Enzyme ◽  
Isolated Mitochondria ◽  
Tissue Homogenates

Abstract Out of several media tested, KCl medium containing BSA was found to be most suitable for isolation of functionally efficient mitochondria from earthworms. Respiration and oxidative phosphorylation in isolated mitochondria are demonstrated in the presence of cytochrome c and BSA in reaction medium. Introduction - The details of the respiratory metabolism in earthworm are yet to be established. There are only a few contradictory reports on the nature of its respiratory enzyme components [1]. While, cytochrome oxidase, succinoxidase, succinate dehydrogenase were identified in earthworm tissue homogenates, the presence of Kreb′s cycle enzymes could not be demonstrated. Very little information is available on earthworm mitochondria except one report where it is isolated in 0.44 ᴍ mannitol [2]. Mitochondria from invertebrates like insects and crustaceans are isolated and characterized [3, 4]. But such methods cannot be extended to earthworms as it is known that conditions for isolation and assay of mitochondria are highly system specific [5].

Oxidative phosphorylation and respiratory control in mitochondria from Aspergillus oryzae

1969 ◽  
Vol 15 (8) ◽  
pp. 975-977 ◽  
Author(s):  
K. Watson ◽  
W. Paton ◽  
J. E. Smith
Keyword(s):  
Bovine Serum Albumin ◽  
Oxidative Phosphorylation ◽  
Aspergillus Oryzae ◽  
Reaction Medium ◽  
Respiratory Control ◽  
Adenosine Diphosphate ◽  
Yeast Mitochondria ◽  
Active Oxidation ◽  
Isolated Mitochondria ◽  
Ph Range

Mitochondria isolated from Aspergillus oryzae exhibited respiratory control with a range of substrates. Bovine serum albumin was required in the reaction medium to observe adenosine diphosphate (ADP) controlled respiration. The mitochondria carried out active oxidation and phosphorylation with citrate as substrate in the pH range 6–7 and showed a slight optimum for oxidative phosphorylation at pH 6.5. The respiratory properties of the isolated mitochondria were similar to those reported for A. niger and yeast mitochondria.

scholarly journals Oxidative phosphorylation during glycollate metabolism in mitochondria from phototrophic Euglena gracilis

1975 ◽  
Vol 150 (3) ◽  
pp. 373-377 ◽  
Author(s):  
N Collins ◽  
R H Brown ◽  
M J Merrett
Keyword(s):  
Cytochrome C ◽  
Oxygen Uptake ◽  
Oxidative Phosphorylation ◽  
Cytochrome C Oxidase ◽  
Electron Acceptor ◽  
Euglena Gracilis ◽  
Gradient Centrifugation ◽  
Antimycin A ◽  
Isolated Mitochondria ◽  
Glycollate Dehydrogenase

Mitochondria were isolated by gradient centrifugation on linear sucrose gradients from broken cell suspensions of phototrophically grown Euglena gracilis. An antimycin A-sensitive but rotenone-insensitive glycollate-dependent oxygen uptake was demonstrated in isolated mitochondria. The partial reactions of glycollate-cytochrome c oxidoreductase and cytochrome c oxidase were demonstrated by using Euglena cytochrome c as exogenous electron acceptor/donor. Isolated mitochondria contain glycollate dehydrogenase and glyoxylate-glutamate aminotransferase and oxidize exogenous glycine. A P:O ratio of 1.7 was obtained for glycollate oxidation, consistent with glycollate electrons entering the Euglena respiratory chain at the flavoprotein level. The significance of these results is discussed in relation to photorespiration in algae.

scholarly journals MEDIATION OF p-AMINODIPHENYLAMINE OXIDATION VIA CYTOCHROME OXIDASE

1962 ◽  
Vol 10 (1) ◽  
pp. 75-78 ◽  
Author(s):  
PHILIP PERSON ◽  
MARVIN S. BURSTONE ◽  
ALBERT S. FINE
Keyword(s):  
Cytochrome C ◽  
Cytochrome Oxidase ◽  
Absorption Spectra ◽  
Heart Muscle ◽  
Ultraviolet Absorption ◽  
Beef Heart ◽  
Respiratory Enzyme ◽  
Tissue Sections ◽  
Fresh Frozen ◽  
Manometric Studies

Manometric studies have revealed that the oxidation of p-aminodiphenylamine by Keilin and Hartree beef heart muscle particles was several-fold higher in the presence of added cytochrome c than in the absence of the pigment. The oxidation of p-aminodiphenylamine was inhibited 90% by 10–4 M cyanide. Correlated spectrophotometric studies demonstrated that the oxidation of p-aminodiphenylamine by Keilin and Hartree particles and fresh-frozen dehydrated tissue sections produced substances with identical visible and ultraviolet absorption spectra. The above experiments further indicate that the oxidation of p-aminodiphenylamine is mediated via cytochrome oxidase, and that this reagent provides valid histochemical localizations of the respiratory enzyme.

Some effects of hypoxia on respiratory metabolism and protein synthesis in rat tissues

1965 ◽  
Vol 209 (2) ◽  
pp. 443-446 ◽  
Author(s):  
A. P. Sanders ◽  
D. M. Hale ◽  
A. T. Miller
Keyword(s):  
Protein Synthesis ◽  
Oxidative Phosphorylation ◽  
Respiratory Control ◽  
Severe Hypoxia ◽  
Rat Tissues ◽  
Tissue Uptake ◽  
Respiratory Metabolism ◽  
Atp Levels ◽  
Tissue Homogenates ◽  
Damaging Effects

Nembutalized rats were pump ventilated with 5% oxygen-95% nitrogen for periods of 60 or 105 min. Samples of liver, kidney, and brain obtained at the end of the period of hypoxia were used for ATP determinations and for polarographic measurements of respiration, respiratory control, and oxidative phosphorylation. In some experiments, leucine-C14 was injected intravenously after 60 min of hypoxia, and tissue uptake and incorporation of leucine into protein determined after an additional 45-min period of hypoxia. After 105 min of hypoxia, brain ATP was reduced 20%, liver ATP 40%, and kidney ATP was unchanged. The incorporation of leucine-C14 into protein was moderately depressed in brain and kidney and almost completely abolished in liver. The polarographic studies indicated that the capacity of tissue homogenates for basal and ADP-stimulated respiration and for oxidative phosphorylation was not impaired by 60 or 105 min of severe hypoxia. It is concluded that the damaging effects of hypoxia, of the severity and duration studied, are due mainly to the reduction in tissue ATP levels rather than to damage of the ATP-producing system.

scholarly journals Resolution and Reconstitution of a Mammalian Membrane

1969 ◽  
Vol 54 (1) ◽  
pp. 38-49 ◽  
Author(s):  
Efraim Racker
Keyword(s):  
Cytochrome C ◽  
Oxidative Phosphorylation ◽  
Succinate Dehydrogenase ◽  
Mitochondrial Membrane ◽  
Inner Mitochondrial Membrane ◽  
Submitochondrial Particles ◽  
Highly Sensitive ◽  
Cytochrome C1 ◽  
Coupling Factors ◽  
Oxidation Chain

The problem of the resolution and reconstitution of the inner mitochondrial membrane has been approached at three levels. (1) Starting with phosphorylating submitochondrial particles, a "resolution from without" can be achieved by stripping of surface components. The most extensive resolution was recently obtained with the aid of silicotungstate. Such particles require for oxidative phosphorylation the addition of several coupling factors as well as succinate dehydrogenase. (2) Starting with submitochondrial particles that have been degraded by trypsin and urea a resolution of the inner membrane proper containing an ATPase has been achieved. These experiments show that at least five components are required for the reconstitution of an oligomycin-sensitive ATPase: a particulate component, F1, Mg++, phospholipids, and Fc. Morphologically, the reconstituted ATPase preparations resemble submitochondrial particles. (3) Starting with intact mitochondria individual components of the oxidation chain have been separated from each other. The following components were required for the reconstitution of succinoxidase: succinate dehydrogenase, cytochrome b\, cytochrome c1, cytochrome c, cytochrome oxidase, phospholipids and Q10. The reconstituted complex had properties similar to those of phosphorylating submitochondrial particles; i.e., the oxidation of succinate by molecular oxygen was highly sensitive to antimycin.

Myocardial ischemia decreases oxidative phosphorylation through cytochrome oxidase in subsarcolemmal mitochondria

1997 ◽  
Vol 273 (3) ◽  
pp. H1544-H1554 ◽  
Author(s):  
E. J. Lesnefsky ◽  
B. Tandler ◽  
J. Ye ◽  
T. J. Slabe ◽  
J. Turkaly ◽  
...  
Keyword(s):  
Cytochrome C ◽  
Myocardial Ischemia ◽  
Oxidative Phosphorylation ◽  
Cytochrome Oxidase ◽  
Morphological Changes ◽  
Maximum Velocity ◽  
Maximal Activity ◽  
Terminal Segment ◽  
Interfibrillar Mitochondria ◽  
Subsarcolemmal Mitochondria

The effect of myocardial ischemia on mitochondrial oxidative phosphorylation was investigated using isolated, buffer-perfused rabbit hearts. After 45 min of global ischemia, oxidative phosphorylation was decreased only in the subsarcolemmal population of mitochondria with all substrates tested. The oxidation of N,N,N',N' tetramethyl p-phenylenediamine-ascorbate, an electron donor to cytochrome oxidase via cytochrome c, was decreased in subsarcolemmal mitochondria [ischemia (n = 6): 76 +/- 3 vs. control (n = 5): 105 +/- 6 nanoatoms O.min-1.mg-1, P < 0.01] but not in interfibrillar mitochondria. Only minor morphological changes were observed by electron microscopy in the isolated mitochondria after ischemia. Neither cytochrome oxidase activity measured under conditions for maximal activity nor the apparent Michaelis constant and maximum velocity values of the two cytochrome c binding sites were different in subsarcolemmal mitochondria isolated from ischemic and control hearts. The cytochrome c content was decreased in subsarcolemmal mitochondria after ischemia (ischemia: 0.111 +/- 0.013 vs. control: 0.156 +/- 0.007 nmol/mg protein, P < 0.05). Thus ischemia decreased the rate of oxidative phosphorylation through cytochrome oxidase selectively in intact subsarcolemmal mitochondria. Ischemic damage to the terminal segment of the electron transport chain involves a decrease in the content of cytochrome c, whereas the expressible catalytic activity of cytochrome oxidase remains unchanged.

Onchocerca fasciata: histochemical demonstration of succinate and NADH dehydrogenase

1996 ◽  
Vol 70 (1) ◽  
pp. 47-51 ◽  
Author(s):  
M.S. Omar ◽  
A.M.S. Raoof
Keyword(s):  
Energy Metabolism ◽  
Oxidative Phosphorylation ◽  
Succinate Dehydrogenase ◽  
Cytochrome Oxidase ◽  
Nadh Dehydrogenase ◽  
Female Worm ◽  
Histochemical Demonstration ◽  
Metabolic Rates ◽  
Respiratory Pathway ◽  
Different Tissues

AbstractThe activities of selected enzymes of the respiratory chain system in Onchocerca fasciata (Filarioidea: Onchocercidae) have been investigated histochemically. Thus, the localization and distributions of NADH dehydrogenase (EC 1.6.99.3), succinate dehydrogenase (SDH) (EC 1.3.99.1) and cytochrome oxidase (EC 1.9.3.1) were investigated in various tissues of the adult female worm by employing MTT, Nitro BT (dehydrogenases) and DAB (cytochrome oxidase). Different tissues varied considerably in their enzymatic activities. The hypodermis and reproductive tissues showed strong and identical localization of NADH and SDH dehydrogenase activities reflecting high metabolic rates. Little or no dehydrogenase activities were observed in the intestine and cuticle. In contrast to the two dehyrogenases, no activity was observed for cytochrome oxidase in any of the tissues in adult or embryonic stages of the worm. The significance of these results with respect to the energy metabolism of the worm is discussed. It is suggested that O. fasciata lacks a classical, mammalian-type respiratory pathway and that oxidative phosphorylation is of no importance as an energy generating pathway in this essentially anaerobic parasite.

scholarly journals Cytochrome oxidase assembly does not require catalytically active cytochrome c.

2003 ◽  
Vol 278 (43) ◽  
pp. 42728
Author(s):  
Antoni Barrientos ◽  
Danielle Pierre ◽  
Johnson Lee ◽  
Alexander Tzagoloff
Keyword(s):  
Cytochrome C ◽  
Cytochrome Oxidase ◽  
Catalytically Active
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