scholarly journals The contribution of the various phosphorylating steps in the respiratory chain to the dinitrophenol-induced ATPase of rat-liver mitochondria

1963 ◽  
Vol 73 (2) ◽  
pp. 311-323 ◽  
Author(s):  
H.C. Hemker
Keyword(s):  
Respiratory Chain ◽  
Rat Liver ◽  
Liver Mitochondria ◽  
Rat Liver Mitochondria

The inhibition of mammalian mitochondrial NADU oxidation by chloramphenicol and its isomers and analogues

1968 ◽  
Vol 46 (9) ◽  
pp. 1003-1008 ◽  
Author(s):  
K. B. Freeman ◽  
D. Haldar
Keyword(s):  
Cytochrome B ◽  
Respiratory Chain ◽  
Rat Liver ◽  
Nadh Dehydrogenase ◽  
Coenzyme Q ◽  
Liver Mitochondria ◽  
Heart Mitochondria ◽  
Rat Liver Mitochondria ◽  
Beef Heart ◽  
Beef Heart Mitochondria

Chloramphenicol and its isomers and analogues have been found to inhibit the oxidation of NADH, but not that of succinate, by beef heart mitochondria. They must therefore inhibit the NADH dehydrogenase segment of the respiratory chain. Chloramphenicol gave 50% inhibition at a concentration of 1 mM. The methylthio analogue of chloramphenicol inhibited NADH – coenzyme Q6 reductase but not NADH–ferricyanide reductase. Spectrophotometric observations suggest that these inhibitors act between NADH and flavin in coupled rat liver mitochondria and between flavin and cytochrome b in uncoupled beef heart mitochondria.

scholarly journals The control of isocitrate oxidation by rat liver mitochondria

1969 ◽  
Vol 114 (2) ◽  
pp. 215-225 ◽  
Author(s):  
D. G. Nicholls ◽  
P. B. Garland
Keyword(s):  
Respiratory Chain ◽  
Rat Liver ◽  
Isocitrate Dehydrogenase ◽  
Adenine Nucleotides ◽  
Kinetic Studies ◽  
Liver Mitochondria ◽  
Rat Liver Mitochondria ◽  
Kinetic Properties ◽  
Dependent Inhibition ◽  
Nad 4

1. The factors capable of affecting the rate of isocitrate oxidation in intact mitochondria include the rate of isocitrate penetration, the activity of the NAD-specific and NADP-specific isocitrate dehydrogenases, the activity of the transhydrogenase acting from NADPH to NAD+, the rate of NADPH oxidation by the reductive synthesis of glutamate and the activity of the respiratory chain. A quantitative assessment of these factors was made in intact mitochondria. 2. The kinetic properties of the NAD-specific and NADP-specific isocitrate dehydrogenases extracted from rat liver mitochondria were examined. 3. The rate of isocitrate oxidation through the respiratory chain in mitochondria with coupled phosphorylation is approximately equal to the maximal of the NAD-specific isocitrate dehydrogenase but at least ten times as great as the transhydrogenase activity from NADPH to NAD+. 4. It is concluded that the energy-dependent inhibition of isocitrate oxidation by palmitoylcarnitine oxidation is due to an inhibition of the NAD-specific isocitrate dehydrogenase. 5. Kinetic studies of NAD-specific isocitrate dehydrogenase demonstrated that its activity could be inhibited by one or more of the following: an increased reduction of mitochondrial NAD, an increased phosphorylation of mitochondrial adenine nucleotides or a fall in the mitochondrial isocitrate concentration. 6. Uncoupling agents stimulate isocitrate oxidation by an extent equal to the associated stimulation of transhydrogenation from NADPH to NAD+. 7. A technique is described for continuously measuring with a carbon dioxide electrode the synthesis of glutamate from isocitrate and ammonia.

Desdanine, an inhibitor of oxidative phosphorylation in mitochondria

1972 ◽  
Vol 18 (2) ◽  
pp. 265-269 ◽  
Author(s):  
Fritz Reusser
Keyword(s):  
Electron Transfer ◽  
Oxidative Phosphorylation ◽  
Respiratory Chain ◽  
Rat Liver ◽  
Mitochondrial Respiration ◽  
Liver Mitochondria ◽  
Rat Liver Mitochondria ◽  
Individual Reaction

The antibiotic, desdanine, acts as an uncoupling agent of oxidative phosphorylation in rat liver mitochondria. In addition, mitochondrial respiration is also impaired but to a lesser degree. Studies of individual reaction sequences occurring within the respiratory chain indicate that desdanine interferes with electron transfer at the flavoprotein regions associated with the oxidation of NADH and succinate. The flavoprotein region associated with the oxidation of succinate is more susceptible to desdanine than the NADH-linked flavoprotein region.

scholarly journals Effect of 2-n-heptyl-4-hydroxyquinoline N-oxide on proton permeability of the mitochondrial membrane

1980 ◽  
Vol 186 (2) ◽  
pp. 637-639 ◽  
Author(s):  
K Krab ◽  
M Wikström
Keyword(s):  
Respiratory Chain ◽  
Rat Liver ◽  
Proton Transport ◽  
Mitochondrial Membrane ◽  
Proton Translocation ◽  
Liver Mitochondria ◽  
Rat Liver Mitochondria ◽  
Proton Permeability ◽  
Isolated Rat Liver ◽  
Isolated Rat

The respiratory-chain inhibitor 2-n-heptyl-4-hydroxyquinoline N-oxide catalyses transmembrane proton transport driven by a pH gradient in isolated rat liver mitochondria. This effect explains the apparent blockade of net proton translocation by this compound in mitochondria respiring with ferrocyanide as described by Papa, Lorusso, Guerrieri, Boffoli, Izzo & Capuano [(1977) in Bioenergetics of Membranes (Packer, Papageorgiu & Trebst, eds.), pp. 377-388, Elsevier/North-Holland, Amsterdam] and by Lorusso, Capuano, Boffoli, Stefanelli & Papa [(1979) Biochem. J. 182, 133-147].

The effect of artichoke (Cynara scolymus L.) extract on respiratory chain system activity in rat liver mitochondria

2010 ◽  
Vol 24 (S2) ◽  
pp. S123-S128 ◽  
Author(s):  
Z. Juzyszyn ◽  
B. Czerny ◽  
Z. Myśliwiec ◽  
A. Pawlik ◽  
M. Droździk
Keyword(s):  
Respiratory Chain ◽  
Rat Liver ◽  
Liver Mitochondria ◽  
Rat Liver Mitochondria ◽  
Cynara Scolymus ◽  
System Activity ◽  
Chain System

scholarly journals The Swelling of Rat Liver Mitochondria by Thyroxine and its Reversal

1959 ◽  
Vol 5 (1) ◽  
pp. 97-108 ◽  
Author(s):  
Albert L. Lehninger ◽  
Betty Lou Ray ◽  
Marion Schneider
Keyword(s):  
Oxidative Phosphorylation ◽  
Temperature Coefficient ◽  
Oxidation State ◽  
Respiratory Chain ◽  
Rat Liver ◽  
Mitochondrial Membrane ◽  
Ph Dependence ◽  
Liver Mitochondria ◽  
The Other ◽  
Rat Liver Mitochondria

The in vitro swelling action of L-thyroxine on rat liver mitochondria as examined photometrically represents an acceleration of a process which the mitochondria are already inherently capable of undergoing spontaneously, as indicated by the identical kinetic characteristics and the extent of thyroxine-induced and spontaneous swelling, the nearly identical pH dependence, and the fact that sucrose has a specific inhibitory action on both types of swelling. However, thyroxine does not appear to be a "catalyst" or coenzyme since it does not decrease the temperature coefficient of spontaneous swelling. The temperature coefficient is very high, approximately 6.0 near 20°. Aging of mitochondria at 0° causes loss of thyroxine sensitivity which correlates closely with the loss of bound DPN from the mitochondria, but not with loss of activity of the respiratory chain or with the efficiency of oxidative phosphorylation. Tests with various respiratory chain inhibitors showed that the oxidation state of bound DPN may be a major determinant of thyroxine sensitivity; the oxidation state of the other respiratory carriers does not appear to influence sensitivity to thyroxine. These facts and other considerations suggest that a bound form of mitochondrial DPN is the "target" of the action of thyroxine. The thyroxine-induced swelling is not reversed by increasing the osmolar concentration of external sucrose, but can be "passively" or osmotically reversed by adding the high-particle weight solute polyvinylpyrrolidone. The mitochondrial membrane becomes more permeable to sucrose during the swelling reaction. On the other hand, thyroxine-induced swelling can be "actively" reversed by ATP in a medium of 0.15 M KCl or NaCl but not in a 0.30 M sucrose medium. The action of ATP is specific; ADP, Mn++, and ethylenediaminetetraacetate are not active. It is concluded that sucrose is an inhibitor of the enzymatic relationship between oxidative phosphorylation and the contractility and permeability properties of the mitochondrial membrane. Occurrence of different types of mitochondrial swelling, the intracellular factors affecting the swelling and shrinking of mitochondria, as well as the physiological significance of thyroxine-induced swelling are discussed.

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