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PubMed1979

[Effect of luliberin on the activities of mitochondrial respiratory enzymes].

Luliberin, a luteinizing hormone-releasing hormone, was shown to inhibit the respiratory enzymes of rat liver mitochondria and submitochondrial particles prepared from beef heart mitochondria. At the hormone concentration of 8.10(-6) M the NADH-oxidase activity of the submitochondrial particles was inhibited by 50%. The fragments of the hormone and its analogs and pyroglutamic acid, oxytocin and bradikinin possessed practically no inhibiting effects. In the case of submitochondrial particles the inhibition was only observed in the presence of Ca2+ and was significantly decreased after addition of bovine serum albumin and phospholipase inhibitors -- butacaine and dicaine. It is assumed that the effect of luliberin on the respiratory chain is mediated through mitochondrial phospholipase.

Animals↗
PubMed1978

The extent of mitochondrial F1-ATPase and adenine nucleotide carrier activity with epsilon-ATP.

1. The use of 1,N6-ethenoadenosine 5'-triphosphate (epsilon-ATP), a synthetic, fluorescent analog of ATP, by whole rat liver mitochondria and by submitochondrial particles produced via sonication has been studied. 2. Direct [3H]adenine nucleotide uptake studies with isolated mitochondria, indicate the epsilon-[3H]ATP is not transported through the inner membrane by the adenine nucleotide carrier and is therefore not utilized by the 2,4-dinitrophenol-sensitive F1-ATPase (EC 3.6.1.3) that functions in oxidative phosphorylation. However, epsilon-ATP is hydrolyzed by a Mg2+-dependent, 2,4-dinitrophenol-insensitive ATPase that is characteristic of damaged mitochondria. 3. epsilon-ATP can be utilized quite well by the exposed F1-ATPase of sonic submitochondrial particles. This epsilon-ATP hydrolysis activity is inhibited by oligomycin and stimulated by 2,4-dinitrophenol. The particle F1-ATPase displays similar Km values for both ATP and epsilon-ATP; however, the V with ATP is approximately six times greater than with epsilon-ATP. 4. Since epsilon-ATP is a capable substrate for the submitochondrial particle F1-ATPase, it is proposed that the fluorescent properties of this ATP analog might be employed to study the submitochondrial particle F1-ATPase complex, and its response to various modifiers of oxidative phosphorylation.

Adenosine Triphosphatases↗
PubMed1983

Surface potential in rat liver mitochondria: terbium ion as a phosphorescent probe for surface potential.

The binding and phosphorescence of Tb3+ in rat liver mitochondria and submitochondrial particles were investigated. Mitochondria were treated briefly with N-ethyl-maleimide (NEM) to prevent phosphate leak and Tb3+ chelation. Up to 30 nmol of Tb3+/mg of protein binds to mitochondrial membranes with high apparent affinity (Kd congruent to 6 microM). Generation of a membrane potential had no significant effect on the apparent affinity or capacity of Tb3+ binding in NEM-treated mitochondria. Mitochondrial bound Tb3+ phosphorescence can be induced selectively by excitation of aromatic amino acid residues. The decay of mitochondrial bound Tb3+ phosphorescence is biphasic. The phosphorescence of the slow phase (t1/2 = 0.45-0.70 ms) is quenched by monovalent salts, indicating a negative surface potential at low salt medium of -5.4 +/- 2.8 mV [10 mM 3-(N-morpholino)-propanesulfonic acid, pH 7.2, 5 microM Tb3+]. In submitochondrial particles, a surface potential of -6.5 +/- 2.7 mV was estimated under the same conditions. Energization did not affect the surface potential significantly in submitochondrial particles and only slightly in mitochondria. Analysis of the phosphorescence of mitochondrial bound Tb3+ reveals two binding sites with high (Kd = 1.5 microM) and low affinity (Kd = 29 microM). The high-affinity site is tentatively identified as the Ca2+ carrier. A fraction of the carrier-bound Tb3+ phosphorescence decays rapidly, presumably as a result of energy transfer to cytochromes in the membrane core. These intramembrane sites appear to move to the surface on the generation of a membrane potential. We conclude that the salt effect on the phosphorescence of the slow phase may serve as a reliable measure of delocalized surface potential in mitochondria and submitochondrial particles. Tb3+ binding to the high-affinity site may be useful as a probe for the mitochondrial Ca2+ translocator.

Animals↗
PubMed1981

Inhibition of coupling factor B activity by cadmium ion, arsenite-2,3-dimercaptopropanol, and phenylarsine oxide, and preferential reactivation by dithiols.

Coupling factor B activity was measured by the stimulation of the ATP-driven NAD+ reduction by succinate or the 32Pi-ATP exchange activity of Factor B-depleted submitochondrial particles. Half-maximal coupling activity was inhibited by 30 microM cadmium, 5 microM phenylarsine oxide, or 0.3 mM arsenite-2,3-dimercaptopropanol. The inhibition was relieved by slight excess of dithiol but not by a 10-fold molar excess of 2-mercaptoethanol. Inhibition of coupling activity by phenylarsine oxide or cadmium was not due to interference in binding of Factor B to depleted particles. Isolated Factor B binds phenylarsine oxide resulting in loss of ability to stimulate depleted submitochondrial particles. The inhibition was largely overcome by dithiol but not by monothiols. The residual coupling activity of depleted submitochondrial particles was highly resistant to cadmium or arsenical. Moreover, binding of arsenical to the depleted particles per se, did not result in inhibition of Factor B-stimulated activity. Furthermore, the addition of phenylarsine oxide to H+-ATPase resulted in loss of Pi-ATP exchange and stimulation of oligomycin-sensitive ATPase activities. Both effects were further potentiated by 2-mercaptoethanol and reversed by dithiols. These effects parallel uncoupling of oxidative phosphorylation in mitochondria by these inhibitors and point to Factor B as the probable component sensitive to these inhibitors.

Adenosine Triphosphatases↗
PubMed1978

Mitochondrial ATPase of Zajdela hepatoma. V. Mitochondria of Zajdela hepatoma contain membrane sectors of ATPase complex unassociated with F1.

Relative content of membrane sectors of ATPase complex in rat liver and Zajdela hepatoma mitochondria and the ability of mitochondrial membrane of the two sources to bind isolated soluble (F1) ATPase were examined. Approximately equal concentrations of oligomycin were required for 50% inhibition of ATPase activity in submitochondrial particles of rat liver and Zajdela hepatoma indicating practically identical content of membrane sectors of ATPase complex in both types of mitochondria. As detected by the increase in oligomycin-sensitive ATPase activity of submitochondrial particles incubated with isolated F1, the submitochondrial particles of Zajdela hepatoma in contrast to those of rat liver were able to bind specifically considerable amounts of exogenously added F1. The results indicate that mitochondria of Zajdela hepatoma contain membrane sectors of ATPase complex unassociated with F1 but capable of association with this enzyme.

Adenosine Triphosphatases↗
PubMed1975

Thermodynamic and EPR characterization of iron-sulfur centers in the NADH-ubiquinone segment of the mitochondrial respiratory chain in pigeon heart.

Several iron-sulfur centers in the NADH-ubiquinone segment of the respiratory chain in pigeon heart mitochondria and in submitochondrial particles were analyzed by the combined application of cryogenic EPR (between 30 and 4.2 degrees K) and potentiometric titration. Center N-1 (iron-sulfur centers associated with NADH dehydrogenase are designated with the prefix "N") resolves into two single electron titratins with EM7.2 values of minus 380 plus or minus 20 mV and minus 240 plus or minus 20 mV (Centers N-1a and N-1b, respectively). Center N-1a exhibits an EPR spectrum of nearly axial symmetry with g parellel = 2.03, g = 1.94, while that of Center N-1b shows more apparent rhombic symmetry with gz = 2.03, gy = 1.94 and gx = 1.91. Center N-2 also reveals EPR signals of axial symmetry at g parallel = 2.05 and g = 1.93 and its principal signal overlaps with those of Centers N-1a and N-1b. Center N-2 can be easily resolved from N-1a and N-1b because of its high EM7.2 value (minus 20 plus or minus 20 mV). Resolution of Centers N-3 and N-4 was achieved potentiometrically in submitochondrial particles. The component with EM7.2 = minus 240 plus or minus 20 mV is defined as Center N-3 (gz = 2.10, (gz = 2.10, (gy = 1.93?), GX = 1.87); the minus 405 plus or minus 20 mV component as Center N-4 (gz = 2.11, (gy = 1.93?), gx = 1.88). At temperatures close to 4.2 degrees K, EPR signals at g = 2.11, 2.06, 2.03, 1.93, 1.90 and 1.88 titrate with EM7.2 = minus 260 plus or minus 20 mV. The multiplicity of peaks suggests the presence of at least two different iron-sulfur centers having similar EM7.2 values (minus 260 plus or minus 20 mV); HENCE, tentatively assigned as N-5 and N-6. Consistent with the individual EM7.2 values obtained, addition of succinate results in the partial reduction of Center N-2, but does not reduce any other centers in the NADH-ubiquinone segment of the respiratory chain. Centers N-2, N-1b, N-3, N-5 and N-6 become almost completely reduced in the presence of NADH, while Centers N-1a and N-4 are only slightly reduced in pigeon heart submitochondrial particles. In pigeon heart mitochondria, the EM7.2 of Center N-4 lies much closer to that of Center N-3, so that resolution of the Center N-3 and N-4 spectra is not feasible in mitochondrial preparations. EM7.2 values and EPR lineshapes for the other iron-sulfur centers of the NADH-ubiquinone segment in the respiratory chain of intact mitochondria are similar to those obtained in submitochondrial particle preparations. Thus, it can be concluded that, in intact pigeon heart mitochondria, at least five iron-sulfur centers show EM7.2 values around minus 250 mV; Center N-2 exhibits a high EM7.2 (minus 20 plus or minus 20 mV), while Center N-1a shows a very low EM7.2 (minus 380 plus or minus 20 mV).

Animals↗
PubMed1987

Inactivation of the mitochondrial ATPase inhibitor protein by chemical modification with diethylpyrocarbonate.

Modification of histidine residue(s) by diethylpyrocarbonate treatment of submitochondrial particles obtained by sonication results in inhibition of ATPase activity and stimulation of oligomycin-sensitive H+ conduction. The inhibition of the ATPase (EC 3.6.1.3) activity persisted in F1 isolated from diethylpyrocarbonate-treated submitochondrial particles, which exhibited the absorbance spectrum of modified histidine. Thus the inhibition of the ATPase activity results from histidine modification in F1 subunits. Removal of the natural inhibitor protein from submitochondrial particles resulted in stimulation of proton conduction. After removal of F1 inhibitor protein from the particles the stimulatory effect exerted by diethylpyrocarbonate treatment on proton conduction was lost. Reconstitution experiments showed that purified F1 inhibitor protein lost, after histidine modification, its capacity to inhibit the ATPase activity and proton conduction. These observations show that the stimulation of proton conduction by the ATPase complex effected by diethylpyrocarbonate treatment results from histidine modification in F1 inhibitor protein.

Animals↗
PubMed1993

Kinetics of inhibition of purified and mitochondrial cytochrome c oxidase by psychosine (beta-galactosylsphingosine).

1. Psychosine (beta-galactosylsphingosine) is the toxic agent in Krabbe's disease (globoid cells leukodystrophy). It inhibits purified bovine heart mitochondrial cytochrome c oxidase; there is a rapid phase of inhibition (complete within 10-15 s) and a slower phase (complete within 10-15 min). Both phases are also seen in rat liver mitochondria. IC50 is about 200 microM psychosine in the purified enzyme and less than 20 microM in mitochondria. Psychosine inhibition is due to binding to cytochrome oxidase, not cytochrome c. 2. Bovine heart submitochondrial particles show inhibition similar to rat liver mitochondria. However, although proteoliposomes containing bovine heart cytochrome oxidase show an identical fast phase, they have no noticeable slow phase of inhibition. Addition of phospholipid liposomes to submitochondrial particles relieved the majority of psychosine inhibition, consistent with the removal of those molecules binding in the slow phase. Psychosine can inhibit cytochrome oxidase molecules facing in either direction in proteoliposomes and submitochondrial particles, suggesting that it can rapidly interact with both sides of a membrane when added externally. 3. At high ionic strength, the presence of psychosine decreases the Vmax. of cytochrome oxidase with little effect on the Km for cytochrome c. This non-competitive inhibition suggests that the psychosine-enzyme complex is kinetically inactive and not labile over the time course of the assay. Psychosine does not inhibit the reduction of haem a or haem a3 by artificial electron donors, but does inhibit the reduction of haem a by cytochrome c.

Animals↗
PubMed1982

Antimycin inhibition as a probe of mitochondrial function in isolated rat hepatocytes. Effects of chronic ethanol consumption.

Previous studies have established that hepatic mitochondria and submitochondrial particles from rats, fed ethanol chronically, display diminished respiratory activities and alterations in the contents of specific electron transfer chain components. The latter include a decrease of about 50% in cytochrome b content. Titrations of respiratory activity in submitochondrial particles with antimycin, a stoichiometric inhibitor of electron flow through the cytochrome b-c1 region of the respiratory chain, indicated a comparable decrease (35%) in the amount of antimycin required to elicit maximal inhibition ('titer') after chronic ethanol treatment. Measurements of antimycin binding to submitochondrial particles by fluorescence quenching demonstrated a similar diminution in the number of tight binding sites per mg protein. By contrast, hepatocytes isolated from control and ethanol-fed rats exhibited nearly identical rates of oxygen utilization under a variety of conditions. However, antimycin titrations of respiratory activity in isolated hepatocytes revealed a 60% decrease in the antimycin titer, but no change in the maximal extent of inhibition after chronic ethanol treatment. Direct measurements of cytochrome b which could be reduced in the presence of antimycin in hepatocytes confirmed a comparable decrease (42%) after chronic ethanol treatment. The results demonstrate that molecular alterations in the cytochrome b region of the respiratory chain caused by ethanol feeding are present in intact liver cells, but suggest that substrate accessibility, rather than the respiratory chain, limits the rate of oxygen utilization in isolated hepatocytes. The data also suggest that mitochondria account for at least 80% of total oxygen utilization by liver cells from both control and ethanol-fed rats.

Alcoholism↗
PubMed1984

Interaction of the aminoglycoside antibiotic dihydrostreptomycin with the H+-ATPase of mitochondria.

In this paper a study is presented of the effect of dihydrostreptomycin on the H+-ATPase of the inner mitochondrial membrane. The antibiotic caused at concentrations of 1-5 X 10(-3)M a marked enhancement of the hydrolytic activity of the H+-ATPase complex in intact mitochondria and submitochondrial particles which was accompanied, in the latter, by enhancement of passive transmembrane proton conduction by the complex. The stimulation by dihydrostreptomycin of ATP hydrolysis resulted in a suppression of the sensitivity of this activity to inhibition by oligomycin. On the other hand the dihydrostreptomycin-promoted proton conduction in submitochondrial particles was suppressed by oligomycin. At concentrations above 10(-2)M dihydrostreptomycin caused inhibition of the activity of both membrane bound and isolated H+-ATPase. In submitochondrial particles devoid of the catalytic moiety (F1) of the H+-ATPase complex, dihydrostreptomycin caused partial inhibition of proton conductivity. It is concluded that the antibiotic uncouples the hydrolytic activity of the catalytic moiety (F1) from transmembrane proton conduction by the membrane sector (F0) of the ATPase complex. This effect can be followed at higher concentrations of dihydrostreptomycin by inhibition of the catalytic activity of F1 and, when F1 is removed from the membrane, by inhibition of transmembrane proton conduction by F0.

Animals↗
PubMed2001

Osmolytes protect mitochondrial F(0)F(1)-ATPase complex against pressure inactivation.

We have previously reported that carbohydrates and polyols protect different enzymes against thermal inactivation and deleterious effects promoted by guanidinium chloride and urea. Here, we show that these osmolytes (carbohydrates, polyols and methylamines) protect mitochondrial F(0)F(1)-ATPase against pressure inactivation. Pressure stability of mitochondrial F(0)F(1)-ATPase complex by osmolytes was studied using preparations of membrane-bound submitochondrial particles depleted or containing inhibitor protein (IP). Hydrostatic pressure in the range from 0.5 to 2.0 kbar causes inactivation of submitochondrial particles depleted of IP (AS particles). However, the osmolytes prevent pressure inactivation of the complex in a dose-dependent manner, remaining up to 80% of hydrolytic activity at the highest osmolyte concentration. Submitochondrial particles containing IP (MgATP-SMP) exhibit low ATPase activity and dissociation of IP increases the hydrolytic activity of the enzyme. MgATP-SMP subjected to pressure (2.2 kbar, for 1 h) and then preincubated at 42 degrees C to undergo activation did not have an increase in activity. However, particles pressurized in the presence of 1.5 M of sucrose or 3.0 M of glucose were protected and after preincubation at 42 degrees C, showed an activation very similarly to those kept at 1 bar. In accordance with the preferential hydration theory, we believe that osmolytes reduce to a minimum the surface of the macromolecule to be hydrated and oppose pressure-induced alterations of the native fold that are driven by hydration forces.

Adenosine Triphosphate↗
PubMed1986

Free-radical-mediated fragmentation of monoamine oxidase in the mitochondrial membrane. Roles for lipid radicals.

A flux of hydroxyl radicals generated by gamma-irradiation can fragment monoamine oxidase in the membrane of submitochondrial particles. This fragmentation can be inhibited by mannitol and in addition is more extensive in monoamine oxidase preparations that have been depleted of lipid. This latter observation is consistent with the higher yields of fragmentation induced by hydroxyl radicals in soluble proteins in the absence of added lipids. In the absence of oxygen, gamma-irradiation of submitochondrial particles leads to cross-linking reactions. A flux of hydroperoxyl radicals also causes fragmentation, whereas one of superoxide is virtually inactive in this respect. The irradiation of submitochondrial particles leads in addition to the accumulation of products of lipid peroxidation. When these irradiated preparations are exposed to ferrous or cupric salts a further fragmentation of monoamine oxidase ensues, especially at acid pH. These transition-metal-catalysed reactions do not occur with irradiated preparations depleted of lipid, and the post-irradiation protein modifications are concomitant with further lipid peroxidation. The data indicate roles for lipid radicals in both fragmentation and cross-linking reactions of proteins in biological membranes. These reactions may have an important bearing on control of protein activity and of protein turnover in membranes.

Animals↗
PubMed1979

[Effect of cobalt and copper complexes with o-phenanthroline on the respiratory activity of mitochondria].

The effects of cobalt and copper complexes with o-phenantroline on the respiratory activity of mitochondria from pea sprouts and submitochondrial particles from bovine heart and on the oxidative phosphorylation in mitochondria were studied. The catalytic activity of the complexes in several components of the respiratory chain autooxidation reactions was investigated. It was shown that the bis (o-phenantroline) cobalt (II) chloride complex is more active in exidation of NADH. The tris (o-phenantroline) cobolt (III) perchlorate complex stimulates the respiratory activity of mitochondria and submitochondrial particles. Possible localization of the effect of this complex was postulated. The (o-phenantroline) copper chloride complex completely inhibits the succinate-dependent respiration of submitochondrial particles and causes disturbances in oxidative phosphorylation of mitochondria.

Animals↗
PubMed1991

Topology of subunits of the mammalian cytochrome c oxidase: relationship to the assembly of the enzyme complex.

The arrangement of three subunits of beef heart cytochrome c oxidase, subunits Va, VIa, and VIII, has been explored by chemical labeling and protease digestion studies. Subunit Va is an extrinsic protein located on the C side of the mitochondrial inner membrane. This subunit was found to label with N-(4-azido-2-nitrophenyl)-2-aminoethane[35S]sulfonate and sodium methyl 4-[3H]formylphenyl phosphate in reconstituted vesicles in which 90% of cytochrome c oxidase complexes were oriented with the C domain outermost. Subunit VIa was cleaved by trypsin both in these reconstituted vesicles and in submitochondrial particles, indicating a transmembrane orientation. The epitope for a monoclonal antibody (mAb) to subunit VIa was lost or destroyed when cleavage occurred in reconstituted vesicles. This epitope was localized to the C-terminal part of the subunit by antibody binding to a fusion protein consisting of glutathione S-transferase (G-ST) and the C-terminal amino acids 55-85 of subunit VIa. No antibody binding was obtained with a fusion protein containing G-ST and the N-terminal amino acids 1-55. The mAb reaction orients subunit VIa with its C-terminus in the C domain. Subunit VIII was cleaved by trypsin in submitochondrial particles but not in reconstituted vesicles. N-Terminal sequencing of the subunit VIII cleavage product from submitochondrial particles gave the same sequence as the untreated subunit, i.e., ITA, indicating that it is the C-terminus which is cleaved from the M side. Subunits Va and VIII each contain N-terminal extensions or leader sequences in the precursor polypeptides; subunit VIa is made without an N-terminal extension.

Amino Acid Sequence↗
PubMed1998

Detection of the local H+ gradients on the internal mitochondrial membrane.

Respiration-dependent responses of a pH probe (fluorescein isothiocyanate, FITC), covalently bound to the membrane proteins of mitochondria and submitochondrial particles (SMP) have been studied. A spectral shift indicating FITC deprotonation was observed when respiration was activated in coupled mitochondria. Such a response was increased by valinomycin and reduced by uncoupler. Some FITC deprotonation was detected in the presence of excess of an uncoupler, but the response was smaller and insensitive to valinomycin. FITC deprotonation was also observed in submitochondrial particles after succinate addition. In this case it was not affected by uncoupler. Increase in the buffer concentration was found to (i) decrease the FITC response and (ii) increase the rate of uncoupled respiration in both mitochondria and submitochondrial particles. The results are consistent with the assumption that respiration initiates appearance of local H+ activity gradients on the inner side of the internal mitochondrial membrane during the steady-state H+ pumping. We suggest that the formation of this gradient is due to kinetic barrier to proton transfer from the bulk phase to the respiratory proton pump vicinity.

Acetone↗
PubMed1981

Selective disaggregation of the H+-translocating ATPase. Isolation of two discrete complexes of the rutamycin-insensitive ATPase differing in mitochondrial membrane-binding properties.

The H+-translocating ATPase from rat liver mitochondria can be disaggregated selectively to yield two distinct, stable complexes of the rutamycin-insensitive ATPase. The two ATPase complexes can be purified to homogeneity by zone sedimentation in a glycerol gradient. Based on their electrophoretic mobility in 5% polyacrylamide gels, the aggregates have been designated as type I (Rf = 0.49) ATPase and type II (Rf = 0.56) ATPase. These two complexes of the ATPase differ in ATP hydrolytic activity, in stability, in mobility on 5% polyacrylamide gel electrophoresis, in subunit composition, and in ability to reassociate with submitochondrial particles which are highly depleted in ATPase activity. The type II ATPase is similar to the F1-ATPase, but the type I ATPase contains a 26.5-kilodalton subunit not present in the type II enzyme. This 26.5-kilodalton subunit is equimolar with the gamma subunit of the ATPase (based on Coomassie blue dye binding); its presence seems to be correlated to the altered properties of the type I ATPase. Type I ATPase reconstitutes rutamycin-sensitive ATPase activity in submitochondrial particles treated with trypsin, urea, ammonia, and 1.5% silicotungstic acid. The type II ATPase does not reconstitute rutamycin-sensitive ATPase activity in these ATPase-depleted submitochondrial particles unless it is supplemented with the 26.5-kilodalton subunit isolated from the type I ATPase. The 26.5-kilodalton protein has thus been functionally identified as important for the binding of the ATPase to the membrane by providing a direct link to the membrane or by binding to the ATPase putting it in an appropriate conformation for binding.

Adenosine Triphosphatases↗
PubMed1980

Generation of superoxide anion by the NADH dehydrogenase of bovine heart mitochondria.

Submitochondrial particles from bovine heart in which NADH dehydrogenase is reduced by either addition of NADH and rotenone or by reversed electron transfer generate 0.9 +/- 0.1 nmol of O2-/min per mg of protein at pH 7.4 and at 30 degrees C. When NADH is used as substrate, rotenone, antimycin and cyanide increase O2- production. In NADH- and antimycin-supplemented submitochondrial particles, rotenone has a biphasic effect: it increases O2- production at the NADH dehydrogenase and it inhibits O2- production at the ubiquinone-cytochrome b site. The generation of O2- by the rotenone, the uncoupler carbonyl cyanide rho-trifluoromethoxyphenylhydrazone and oligomycin at concentrations similar to those required to inhibit energy-dependent succinate-NAD reductase. Cyanide did not affect O2- generation at the NADH dehydrogenase, but inhibited O2- production at the ubiquinone-cytochrome b site. Production of O2- at the NADH dehydrogenase is about 50% of the O2- generation but the ubiquinone-cytochrome b area at pH 7.4. Additivity of the two mitochondrial sites of O2- generation was observed over the pH range from 7.0 to 8.8. AN O2- -dependent autocatalytic process that requires NADH, submitochondrial particles and adrenaline is described.

Animals↗