Heart mitochondria

Citric acid cycle components (from rat heart mitochondria). 

Cytochrome c oxidase (from bovine heart mitochondria). [9001-16-5] Mr 100,0007haeme,... 

The standard free energy change, AG°, for this reaction is + 6.7 kj/mol. However, the observed free energy change (AG) for this reaction in pig heart mitochondria is +0.8 kj/mol. What is the ratio of [isocitrate]/[citrate] in these mitochondria If [isocitrate] = 0.03 mM, what is [citrate] ... 

L., and Deiscnhofer, J, 1997. The crystal strnctnrc of the cytochrome bci complex from bovine heart mitochondria. Science 277 60-66.])... 

Abrahams, J.P.. Leslie, A.G.W., Luner, R., Walker, J.E. (1994). Structure at 2.8A resolution of FpATPase from bovine heart mitochondria. Nature 370, 621-628. 

Fig. 18. pH dependence of the oxidized Rieske fragment from bovine heart mitochondria (ISF). (a) Redox potential determined by cyclic voltammetry. The line was fitted to the data points, giving = 7.6 and pi a, x2 = 9-2. (b) CD intensity of the oxidized... 

Fig. 5. Structural comparison of the water-soluble fragments of the Rieske proteins from (a) spinach chloroplasts and (b) beef heart mitochondria. Conserved smd vEiriable regions are highlighted and the conserved /3-loop discussed in Fig. 6 is denoted by darker gray on the rear of the molecules.

Fig. 6. Sequence comparisons of Rieske proteins from spinach chloroplasts, beef heart mitochondria, green sulfur bacteria, and firmicutes. The extended insertion of proteobacterial Rieske proteins as compared to the mitochondrial one is indicated by a dotted arrow. The redox-potential-influencing Ser residue is marked by a vertical arrow. The top and the bottom sequence numberings refer to the spinach and bovine proteins, respectively. Fully conserved residues are marked by dark shading, whereas the residues conserved in the b6f-group are denoted by lighter shading.

Barker CD, Reda T, Hirst J. 2007. The flavoprotein suhcomplex of complex I (NADH ubiquinone oxidoreductase) from bovine heart mitochondria Insights into the mechanisms of NADH oxidation and NAD reduction from protein film voltammetry. Biochemistry 46 3454-3464. 

Human heart mitochondria Ammonium acetate Biphasic QSTAR SONAR (Gaucher et al., 2004)... 

Albracht, S.P.J., Van Verseveld, H.W., Hagen, W.R., and Kalkman, M.L. 1980. A comparison of the respiratory chain in particles from Paracoccus denitrificans and bovine heart mitochondria by EPR spectroscopy. Biochimica et Biophysica Acta 593 173-186. 

Joshi, S., and Burrows, R. (1990) ATP synthase complex from bovine heart mitochondria. J. Biol. Chem. 265,14518-14525. 

Such a process is supposed to occur within the limits of Q-cycle mechanism (Figure 23.2). In accord with this scheme ubihydroquinone reduced dioxygen in Complex III, while superoxide producers in Complex I could be FMN or the FeS center [12]. Zhang et al. [24] also suggested that the Q-cycle mechanism is responsible for the superoxide production by the succinate-cytochrome c reductase in bovine heart mitochondria and that FAD of succinate dehydrogenase is another producer of superoxide. Young et al. [25] concluded that, in addition to Complex III, flavin-containing enzymes and FeS centers are also the sites of superoxide production in liver mitochondria. 

This mechanism is now considered to be of importance for the protection of LDL against oxidation stress, Chapter 25.) The antioxidant effect of ubiquinones on lipid peroxidation was first shown in 1980 [237]. In 1987 Solaini et al. [238] showed that the depletion of beef heart mitochondria from ubiquinone enhanced the iron adriamycin-initiated lipid peroxidation whereas the reincorporation of ubiquinone in mitochondria depressed lipid peroxidation. It was concluded that ubiquinone is able to protect mitochondria against the prooxidant effect of adriamycin. Inhibition of in vitro and in vivo liposomal, microsomal, and mitochondrial lipid peroxidation has also been shown in studies by Beyer [239] and Frei et al. [240]. Later on, it was suggested that ubihydroquinones inhibit lipid peroxidation only in cooperation with vitamin E [241]. However, simultaneous presence of ubihydroquinone and vitamin E apparently is not always necessary [242], although the synergistic interaction of these antioxidants may take place (see below). It has been shown that the enzymatic reduction of ubiquinones to ubihydroquinones is catalyzed by NADH-dependent plasma membrane reductase and NADPH-dependent cytosolic ubiquinone reductase [243,244]. 

High antioxidative activity carvedilol has been shown in isolated rat heart mitochondria [297] and in the protection against myocardial injury in postischemic rat hearts [281]. Carvedilol also preserved tissue GSL content and diminished peroxynitrite-induced tissue injury in hypercholesterolemic rabbits [298]. Habon et al. [299] showed that carvedilol significantly decreased the ischemia-reperfusion-stimulated free radical formation and lipid peroxidation in rat hearts. Very small I50 values have been obtained for the metabolite of carvedilol SB 211475 in the iron-ascorbate-initiated lipid peroxidation of brain homogenate (0.28 pmol D1), mouse macrophage-stimulated LDL oxidation (0.043 pmol I 1), the hydroxyl-initiated lipid peroxidation of bovine pulmonary artery endothelial cells (0.15 pmol U1), the cell damage measured by LDL release (0.16 pmol l-1), and the promotion of cell survival (0.13 pmol l-1) [300]. SB 211475 also inhibited superoxide production by PMA-stimulated human neutrophils. 

Figure 5.20 The X-ray structure of the FrATP synthase from bovine heart mitochondria. The a, (3 and y subunits are in red, yellow and blue, respectively. The inset (bottom left) shows the orientation of the subunits in this view. The bar is 20 A long. (From Voet and Voet, 2004. Reproduced with permission from John Wiley Sons., Inc.)...

Beyer, K., KUngenberg, M., 1985, ADP/ATP carrier protein from beef heart mitochondria has high amounts oftightly bound cardioUpin, as revealed by P nuclear magnetic resonance. Biochemistry 24 3821-3826. 

Beyer, K., and Nuscher, B., 1996, Specific cardiolipin binding interferes with labeling of sulfhydryl residues in the adenosine diphosphate/adenosine triphosphate carrier protein from beef heart mitochondria, Biochemistry 35 15784-15790. 

As shown in Table 1, the acyl moiety of cardiolipin is comprised almost entirely of unsaturated fatty acids. Other membrane phospholipids such as phosphatidyl choline and phosphatidyl ethanolamine contain 1(M0 mol of saturatedfatty acids such as palmitic acid (Ci6 0) and stearic acid (Ci8 0) per 100 mol of total fatty acids. In particular,linoleic acid (Cl8 2) is the most abundant polyunsaturated fatty acid consisting of 80 mol%, linolenic acid (Cl8 3) 8 mol%, and oleic acid (Ci8 i) 6 mol%. Therefore, by using a commercially available cardiolipin purified from bovine heart mitochondria, we characterized auto-oxidation products by reverse phase HPTLC and reverse phase HPLC. 

Table I. Fatty acy molecular species of cardiolipin from bovine heart mitochondria (slightly...

It is well recognized that activity of many mitochondrial enzymes is modulated by the mitochondrial acidic phospholipid cardiolipin. Adenine nucleotide translocase (ANT) of bovine heart mitochondria is known to be tightly associated with six molecules of cardiolipin (Beyer and Klingenberg, 1985), and cardiolipin is absolutely required for the ANT activity (Hoffmann et al, 1994). ADP control of the carrier transition was gradually lost after phospholipase treatment and the ADP conttol could be fully restored through the addition of cardiolipin (Beyer and Nuscher, 1996). Cardiolipin-mediated activation of cytochrome c oxidase (Abramovitch et al, 1990) and... 

Figure 1. EPR absorption derivative spectrum of aconitase (as isolated from beef heart mitochondria) in 100 mM potassium phosphate, pH 7.0. Experimental conditions for obtaining the EPR spectrum were 10 K, 100 microwatts power, 0.8 milliTesla (mT) modulation amplitude, and 9.42 GHz microwave frequency.

Figure 2. Zero-field MSssbauer spectra of dithionite reduced three-iron clusters of (A) D. gigas ferredoxin n, (B) A. vinelandii ferredoxin I, and (C) aconitase isolated from beef heart mitochondria. (Reproduced with permission fixim Ref. 38. Copyright 1982 Elsevier.)...

Gardner, J. F., and Boveris, A. (1990). Generation of superoxide anion by the NADH dehydrogenase of bovine heart mitochondria. Biochem. ]. 191, 421-427-... 

Gellerich, F.N. Laterveer, F.D. Korzeniewski, B. Zierz, S. Nicolay, K. Dextran strongly increases the Michaelis constants of oxidative phosphorylation and of mitochondrial creatine kinase in heart mitochondria. Eur. J. Biochem., 254, 172-180 (1998)... 

Albrecht, G.J. Purification and properties of nucleoside triphosphate-adenosine monophosphate transphosphorylase from beef heart mitochondria. Biochemistry, 9, 2462-2470 (1970)... 

Wieland, B. Tomasselli, A.G. Noda, L.H. Frank, R. Schulz, G.E. The amino acid sequence of GTP AMP phosphotransferase from beef-heart mitochondria. Extensive homology with cytosolic adenylate kinase. Eur. J. Biochem., 143, 331-339 (1984)... 

Cytochrome c oxidase (from bovine heart mitochondria). [9001-16-5] Mr 100,000/haeme, [EC 1.9.3.1]. Purified by selective solubilisation with Triton X-100 and subsequently with lauryl maltoside finally by sucrose gradient centrifugation [Li et al. BJ 242 417 1978],... 

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