Repeatability of the Submitochondrial Particle Assay

2002 ◽  
Vol 53 (1) ◽  
pp. 122-128 ◽  
Author(s):  
F Doherty
Keyword(s):  
Submitochondrial Particle

scholarly journals A kinetic analysis of the changes in fluorescence on the interaction of 8-anilinonaphthalene-l-sulphonate with submitochondrial particles

1976 ◽  
Vol 158 (2) ◽  
pp. 295-305 ◽  
Author(s):  
N Gains ◽  
A P Dawson
Keyword(s):  
Kinetic Analysis ◽  
Mitochondrial Membrane ◽  
Antimycin A ◽  
Submitochondrial Particles ◽  
Submitochondrial Particle ◽  
Fluorescence Change

A comparison of the fluorescence change on the addition of 8-anilinonaphthalene-1-sulphonate to succinate-energized submitochondrial particles with that on the addition of succinate to submitochondrial particles incubated with 8-anilinonaphthalene-1-sulphonate shows that these changes in fluorescence may be explained solely in terms of 8-anilinonaphthalene-1-sulphonate binding. This comparison does not support the proposal of an 8-anilinonaphthalene-1-sulphonate-monitored change in the conformation of submitochondrial-particle membranes [Brocklehurst, Freedman, Hancock & Radda (1970) Biochem. J.116, 721-731]. The biphasic nature of the decrease in fluorescence, which was found to follow the addition of uncoupler to submitochondrial particles incubated with ATP or succinate, or of antimycin A to submitochondrial particles incubated with succinate, does not support the existence of ‘aplectic’ and ‘symplectic’ states of the mitochondrial membrane [Barrett-Bee & Radda (1972) Biochim, Biophys. Acta 267, 211-215].

scholarly journals A comparison of the effects of NN′-dicyclohexylcarbodi-imide, oligomycin A and aurovertin on energy-linked reactions in mitochondria and submitochondrial particles

1968 ◽  
Vol 108 (3) ◽  
pp. 445-456 ◽  
Author(s):  
A. M. Roberton ◽  
Caroline T. Holloway ◽  
I G Knight ◽  
R B Beechey
Keyword(s):  
Potent Inhibitor ◽  
Atp Synthesis ◽  
Mitochondrial Fraction ◽  
Optimum Concentration ◽  
Submitochondrial Particles ◽  
Nicotinamide Nucleotide Transhydrogenase ◽  
Oligomycin A ◽  
Submitochondrial Particle ◽  
Site Of Action ◽  
Stimulation Of

1. The effects of dicyclohexylcarbodi-imide, oligomycin A and aurovertin on enzyme systems related to respiratory-chain phosphorylation were compared. Dicyclohexylcarbodi-imide and oligomycin A have very similar functional effects, giving 50% inhibition of ATP-utilizing and ATP-generating systems at concentrations below 0·8nmole/mg. of submitochondrial-particle protein. Aurovertin is a more potent inhibitor of ATP synthesis, giving 50% inhibition at 0·2nmole/mg. of protein. However, aurovertin is a less potent inhibitor of ATP-utilizing systems: the ATP-driven energy-linked nicotinamide nucleotide transhydrogenase is 50% inhibited at 3·0nmoles/mg. of protein and the ATP-driven reduction of NAD+ by succinate is 50% inhibited at 0·95nmole/mg. of protein. 2. With EDTA-particles (prepared by subjecting mitochondria to ultrasonic radiation at pH9 in the presence of 2mm-EDTA) the maximum stimulation of the ATP-driven partial reactions is effected by similar concentrations of oligomycin A and dicylcohexylcarbodi-imide, but the latter is less effective. The stimulatory effects of suboptimum concentrations of dicyclohexylcarbodi-imide and oligomycin A are additive. Aurovertin does not stimulate these reactions or interfere with the stimulation by the other inhibitors. 3. Dicyclohexylcarbodi-imide and oligomycin A stimulate the aerobic energy-linked nicotinamide nucleotide transhydrogenase of EDTA-particles, but the optimum concentration is higher than that required for the ATP-driven partial reactions. Aurovertin has no effect on this reaction. 4. The site of action of dicyclohexylcarbodi-imide is in CF0, the mitochondrial fraction that confers oligomycin sensitivity on F1 mitochondrial adenosine triphosphatase.

Comparison of in vitro submitochondrial particle and Microtox® assays for determining the toxicity of organotin compounds

1998 ◽  
Vol 17 (6) ◽  
pp. 1005-1012 ◽  
Author(s):  
Emanuele Argese ◽  
Cinzia Bettiol ◽  
Annamaria Volpi Ghirardini ◽  
Matteo Fasolo ◽  
Gianumberto Giurin ◽  
...  
Keyword(s):  
Organotin Compounds ◽  
Submitochondrial Particle

Profile of toxic response to sediments using whole-animal and in vitro submitochondrial particle (SMP) assays

1996 ◽  
Vol 15 (3) ◽  
pp. 319-324 ◽  
Author(s):  
Alan D. Bettermann ◽  
Jonathan C. Dorofi ◽  
James M. Lazorchak
Keyword(s):  
Toxic Response ◽  
Submitochondrial Particle

Study on the toxicity of phenolic and phenoxy herbicides using the submitochondrial particle assay

2005 ◽  
Vol 19 (8) ◽  
pp. 1035-1043 ◽  
Author(s):  
E. Argese ◽  
C. Bettiol ◽  
D. Marchetto ◽  
S. De Vettori ◽  
A. Zambon ◽  
...  
Keyword(s):  
Submitochondrial Particle ◽  
Phenoxy Herbicides

Effects of antibodies to intact cytochrome-c oxidase and its subunit V on the enzymatic activity

1988 ◽  
Vol 66 (11) ◽  
pp. 1218-1225 ◽  
Author(s):  
P. Nicholls ◽  
C. E. Cooper ◽  
J. A. Freedman ◽  
B. D. Leece
Keyword(s):  
Cytochrome C ◽  
Cytochrome C Oxidase ◽  
Membrane System ◽  
State Change ◽  
Submitochondrial Particles ◽  
Biphasic Pattern ◽  
Competitive Kinetics ◽  
Submitochondrial Particle ◽  
Enzyme Subunits ◽  
Functional Membrane

Antibodies have been raised in rabbits against whole beef heart cytochrome-c oxidase and purified subunit V. Antioxidase recognizes nearly all the enzyme subunits but reacts very strongly with subunits II and IV. Antisubunit V is quite specific against subunit V. Inhibition of enzyme activity by antioxidase is typically biphasic in time, indicating populations of both rapidly and slowly reacting molecules. Variation of cytochrome c concentration shows partially competitive kinetics, but the antibody also affects "internal" enzymatic events, including the catalytic turnover induced by N,N,N′,N′-tetramethyl-p-phenylenediamine alone and the spin-state change in cytochrome a3 that follows reduction of cytochrome a. No spectral effects can be seen however. Antioxidase also inhibits proteoliposomal respiration with external cytochrome c, but not that with internally trapped cytochrome c. No functionally significant epitopes are detectable on the N side of the membrane in proteoliposomes, although some small effects can be seen with submitochondrial particles. Antisubunit V inhibits the isolated enzyme by at least 60%. The inhibition at high ionic strength induces a biphasic pattern with respect to cytochrome c concentration. Antisubunit V may thus slow the dissociation of cytochrome c from its complex with the enzyme. Antisubunit V has only small effects on the activities of proteoliposomal and submitochondrial particle oxidase in either orientation. On subunit V, some sites, the binding of which can give rise to inhibition, are thus not accessible to antisubunit V when the enzyme is embedded in a functional membrane system.

scholarly journals Chymotrypsin activates cardiac mitochondrial carnitine-acylcarnitine translocase

1989 ◽  
Vol 261 (2) ◽  
pp. 363-370 ◽  
Author(s):  
P E Wolkowicz ◽  
D F Pauly ◽  
W B Van Winkle ◽  
J B McMillin
Keyword(s):  
Ultrastructural Changes ◽  
Maximal Velocity ◽  
Mitochondrial Matrix ◽  
Beta Oxidation ◽  
Passive Permeability ◽  
Inhibitor Binding ◽  
Maximal Inhibition ◽  
Binding Properties ◽  
Submitochondrial Particle ◽  
Acylcarnitine Translocase

The carnitine-acylcarnitine translocase facilitates carnitine and acylcarnitine transport into the mitochondrial matrix during beta-oxidation. Our results demonstrate that chymotrypsin can activate the maximal velocity of N-ethylmaleimide (NEM)-sensitive carnitine or palmitoylcarnitine exchange 7-fold, while doubling the affinity of the translocase for carnitine. Chymotrypsin activation is strictly dependent on the presence of free or short-chain acylcarnitine in the proteolysis medium, the extent of activation decreasing as the acylcarnitine chain length in the proteolysis medium increases. Chymotrypsin treatment decreases the apparent I50 value (inhibitor concentration required to give half-maximal inhibition) of the translocase for inhibition by NEM only under conditions which produce translocase activation. Modification of submitochondrial particle membranes by chymotrypsin does not result in gross ultrastructural changes or in an increase in the passive permeability of these membranes to carnitine. The data suggest that carnitine binding produces a change in translocase conformation which allows chymotrypsin modification to occur. This modification alters the kinetic and inhibitor-binding properties of the translocase.

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