Fumarate reductase activity of bovine heart succinate-ubiquinone reductase. New assay system and overall properties of the reaction

Grivennikova, Vera G.; Gavrikova, Eleonora V.; Тимошин, А. А.; Vinogradov, Andrei D.

doi:10.1016/0005-2728(93)90067-p

Cited by 36 publications

(32 citation statements)

References 58 publications

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“…Structural divergence in trypanosomatid SDH3 and SDH4 could be the cause for lower binding affinities for both quinones and inhibitors. In addition, we found for the dicarboxylate-binding site that the IC 50 value for malonate (40 M) was much higher than the K i value for bovine Complex II (1.3 M) (45).…”

Section: Resultsmentioning

confidence: 68%

“…7), indicating that the 6-polyprenyl group of ubiquinone contributes to the binding affinity. The apparent V max value of the T. cruzi Complex II was rather constant, 11.9 Ϯ 2.2 for Q 1 and 11.5 Ϯ 0.4 Q 2 units/mg proteins, respectively, and one-fourth of those reported for bovine and E. coli enzymes (45,46). This is not surprising because T. cruzi complex II has about 2-3 times more proteins than the other enzymes.…”

Section: Resultsmentioning

confidence: 75%

“…This is not surprising because T. cruzi complex II has about 2-3 times more proteins than the other enzymes. K m values for ubiquinone and succinate (18.8 Ϯ 6.4 M (Q 2 ) and 1.48 Ϯ 0.17 mM, respectively) were higher than 0.3 and 130 M, respectively, of bovine enzyme (45), and 2 and 277 M, respectively, of the E. coli enzyme (46,47). Notably, the K m value for succinate was comparable with 610 M in adult A. suum (10), which expresses the stage-specific Complex II as quinol:fumarate reductase under hypoxic habitats in host organisms.…”

Section: Resultsmentioning

confidence: 77%

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Novel Mitochondrial Complex II Isolated from Trypanosoma cruzi Is Composed of 12 Peptides Including a Heterodimeric Ip Subunit

Morales

Mogi

Mineki

et al. 2009

Journal of Biological Chemistry

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Mitochondrial respiratory enzymes play a central role in energy production in aerobic organisms. They differentiated from the ␣-proteobacteria-derived ancestors by adding noncatalytic subunits. An exception is Complex II (succinate: ubiquinone reductase), which is composed of four ␣-proteobacteria-derived catalytic subunits (SDH1-SDH4). Complex II often plays a pivotal role in adaptation of parasites in host organisms and would be a potential target for new drugs. We purified Complex II from the parasitic protist Trypanosoma cruzi and obtained the unexpected result that it consists of six hydrophilic (SDH1, SDH2 N , SDH2 C , and SDH5-SDH7) and six hydrophobic (SDH3, SDH4, and SDH8 -SDH11) nucleus-encoded subunits. Orthologous genes for each subunit were identified in Trypanosoma brucei and Leishmania major. Notably, the iron-sulfur subunit was heterodimeric; SDH2 N and SDH2 C contain the plant-type ferredoxin domain in the N-terminal half and the bacterial ferredoxin domain in the C-terminal half, respectively. Catalytic subunits (SDH1, SDH2 N plus SDH2 C , SDH3, and SDH4) contain all key residues for binding of dicarboxylates and quinones, but the enzyme showed the lower affinity for both substrates and inhibitors than mammalian enzymes. In addition, the enzyme binds protoheme IX, but SDH3 lacks a ligand histidine. These unusual features are unique in the Trypanosomatida and make their Complex II a target for new chemotherapeutic agents.The parasitic protist Trypanosoma cruzi is the etiological agent of Chagas disease, a public health threat in Central and South America. These parasites are normally transmitted by reduviid bugs via the vector feces after a bug bite and also via transfusion of infected blood. About 16 -18 million people are infected, and 100 million are at risk, but there are no definitive chemotherapeutic treatments available (1). Despite having potential pathways for oxidative phosphorylation (2), all trypanosomatids (Trypanosoma and Leishmania species) analyzed so far are characterized by incomplete oxidation of glucose with secretion of end products, such as succinate, alanine, ethanol, acetate, pyruvate, and glycerol (3, 4) (Fig. 1). Major routes for formation of succinate in Trypanosoma brucei are via NADH-dependent fumarate reductase in glycosomes and mitochondria (5, 6). In trypanosomatid mitochondria, the Krebs cycle is inefficient, and pyruvate is principally converted to acetate via acetate:succinate CoA transferase (7). A part of the Krebs cycle operates the utilization of histidine in the insect stage of T. cruzi (8).Mitochondrial Complex II (succinate:quinone reductase (SQR) 5 and succinate dehydrogenase (SDH)) serves as a membrane-bound Krebs cycle enzyme and often plays a pivotal role in adaptation of parasites to environments in their host (9, 10). In general, Complex II consists of four subunits (11). A flavoprotein subunit (SDH1, Fp) and an iron-sulfur subunit (SDH2, Ip) form a soluble heterodimer, which then binds to a membrane anchor heterodimer, SDH3 (CybL) and SDH4 (CybS)....

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Section: Resultsmentioning

confidence: 68%

Section: Resultsmentioning

confidence: 75%

Section: Resultsmentioning

confidence: 77%

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Novel Mitochondrial Complex II Isolated from Trypanosoma cruzi Is Composed of 12 Peptides Including a Heterodimeric Ip Subunit

Morales

Mogi

Mineki

et al. 2009

Journal of Biological Chemistry

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“…Measurement of Enzyme Activity-Activity measurements for the succinate oxidase reaction were measured in the presence of 10 mM succinate in the assay cuvette as previously described (29) ) was used as final electron acceptor with varied amounts of quinone as previously described (29,30).…”

Section: Methodsmentioning

confidence: 99%

Retention of Heme in Axial Ligand Mutants of Succinate-Ubiquinone Oxidoreductase (Complex II) from Escherichia coli

Maklashina

Rothery

Weiner

et al. 2001

Journal of Biological Chemistry

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Succinate-ubiquinone oxidoreductase (SdhCDAB, complex II) from Escherichia coli is a four-subunit membrane-bound respiratory complex that catalyzes ubiquinone reduction by succinate. In the E. coli enzyme, heme b 556 is ligated between SdhC His 84 and SdhD His 71 . Contrary to a previous report (Vibat, C. R. T., Cecchini, G., Nakamura, K., Kita, K., and Gennis, R. B. (1998) Biochemistry 37, 4148 -4159), we demonstrate the presence of heme in both SdhC H84L and SdhD H71Q mutants of SdhCDAB. EPR spectroscopy reveals the presence of low spin heme in the SdhC H84L (g z ‫؍‬ 2.92) mutant and high spin heme in the SdhD H71Q mutant (g ‫؍‬ 6.0). The presence of low spin heme in the SdhC H84L mutant suggests that the heme b 556 is able to pick up another ligand from the protein. CO binds to the reduced form of the mutants, indicating that it is able to displace one of the ligands to the low spin heme of the SdhC H84L mutant. The g ‫؍‬ 2.92 signal of the SdhC H84L mutant titrates with a redox potential at pH 7.0 (E m,7 ) of approximately ؉15 mV, whereas the g ‫؍‬ 6.0 signal of the SdhD H71Q mutant titrates with an E m,7 of approximately ؊100 mV. The quinone site inhibitor pentachlorophenol perturbs the heme optical spectrum of the wild-type and SdhD H71Q mutant enzymes but not the SdhC H84L mutant. This finding suggests that the latter residue also plays an important role in defining the quinone binding site of the enzyme. The SdhC H84L mutation also results in a significant increase in the K m and a decrease in the k cat for ubiquinone-1, whereas the SdhD H71Q mutant has little effect on these parameters. Overall, these data indicate that SdhC His 84 has an important role in defining the interaction of SdhCDAB with both quinones and heme b 556 .Succinate-ubiquinone oxidoreductases (SQR 1 ; succinate dehydrogenase, complex II) and menaquinol-fumarate reductase (QFR; fumarate reductase) are membrane-bound complexes that play critical roles in cellular metabolism in prokaryotic and eukaryotic organisms. The enzymes catalyze the reversible transfer of two electrons and two protons between succinatefumarate and the quinol-quinone couples (1); however, they normally are only expressed in aerobic (SQR) or anaerobic (QFR) environments (2, 3). SQR directly connects the Krebs cycle with the aerobic respiratory chain by transferring reducing equivalents via quinone, whereas QFR is a terminal reductase in anaerobic respiration, where it oxidizes low potential quinols and reduces fumarate as the final electron acceptor (2, 4 -6).Two distinct operons encode the subunits of SQR (sdhCDAB) (7, 8) and QFR (frdABCD) (9, 10) in Escherichia coli. X-ray structures for membrane-bound QFR from E. coli (11) 1ϩ,0 ). The soluble dehydrogenase fragment (FpIp) binds to the hydrophobic anchor domain to form a membrane-bound complex (complex II) that is able to carry out electron transfer with quinone-quinol. The hydrophobic membrane anchor subunit pairs (SdhC, FrdC and SdhD, FrdD) are essential for forming the quinone binding sites and assembly of t...

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“…It was found [53] that the mitochondrial succinate dehydrogenase is strongly inhibited by oxaloacetate. To take this fact into account we have assumed that catalytically active succinate dehydrogenase, SDH, could bind oxaloacetate to form a catalytically inactive complex, SDH-OAA.…”

Section: Succinate Dehydrogenase (Sdh)mentioning

confidence: 99%

Kinetic Model of Mitochondrial Krebs Cycle: Unraveling the Mechanism of Salicylate Hepatotoxic Effects

2006

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This paper studies the effect of salicylate on the energy metabolism of mitochondria using in silico simulations. A kinetic model of the mitochondrial Krebs cycle is constructed using information on the individual enzymes. Model parameters for the rate equations are estimated using in vitro experimental data from the literature. Enzyme concentrations are determined from data on respiration in mitochondrial suspensions containing glutamate and malate. It is shown that inhibition in succinate dehydrogenase and α-ketoglutarate dehydrogenase by salicylate contributes substantially to the cumulative inhibition of the Krebs cycle by salicylates. Uncoupling of oxidative phosphorylation has little effect and coenzyme A consumption in salicylates transformation processes has an insignificant effect on the rate of substrate oxidation in the Krebs cycle. It is found that the salicylate-inhibited Krebs cycle flux can be increased by flux redirection through addition of external glutamate and malate, and depletion in external α-ketoglutarate and glycine concentrations.

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Fumarate reductase activity of bovine heart succinate-ubiquinone reductase. New assay system and overall properties of the reaction

Cited by 36 publications

References 58 publications

Novel Mitochondrial Complex II Isolated from Trypanosoma cruzi Is Composed of 12 Peptides Including a Heterodimeric Ip Subunit

Novel Mitochondrial Complex II Isolated from Trypanosoma cruzi Is Composed of 12 Peptides Including a Heterodimeric Ip Subunit

Retention of Heme in Axial Ligand Mutants of Succinate-Ubiquinone Oxidoreductase (Complex II) from Escherichia coli

Kinetic Model of Mitochondrial Krebs Cycle: Unraveling the Mechanism of Salicylate Hepatotoxic Effects

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