Mitochondrial Products of Yeast Atpase and Cytochrome Oxidase

Tzagoloff, Alexander; Akai, Anna; Rubin, Meryl S.

doi:10.1016/b978-0-12-426750-3.50042-1

Cited by 33 publications

(39 citation statements)

References 25 publications

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“…The functional groups of the native enzyme are heme a (cytochromes a and a3) and copper. Following depolymerization of cytochrome oxidase with denaturing agents, heme a has been found to copurify with subunit 1 (40,000 daltons) (33) and subunit 7 (9,000 daltons) (34) which suggests that they are the hemoprotein components of the complex. In general, however, the precise relationship of the redox carriers to the enzyme subunits is still not agreed upon.…”

Section: Identity Of Mitochondrial Productsmentioning

confidence: 99%

“…They are highly insoluble in water and tend to form large aggregates that can only be dispersed by means of powerful ionic detergents. These properties have been attributed to their high content of non polar amino acids (32,33,64,75,76). The mitochondrially synthesized subunits of cytochrome oxidase, for example, average 10-15% more nonpolar residues than do the other four subunits of the enzyme (32,33,75,76).…”

Section: Properties Of Mitochondrial Productsmentioning

confidence: 99%

“…These properties have been attributed to their high content of non polar amino acids (32,33,64,75,76). The mitochondrially synthesized subunits of cytochrome oxidase, for example, average 10-15% more nonpolar residues than do the other four subunits of the enzyme (32,33,75,76). The ATPase proteolipid is an even more extreme case, having only 23% polar amino acids (64)-this is to be contrasted with values of 50-60% observed in most water soluble proteins (77).…”

Section: Properties Of Mitochondrial Productsmentioning

confidence: 99%

“…Both cytochrome oxidase (33) and coenzyme QHrcytochrome c reductase (43,44) contain at least one hemoprotein carrier synthesized in mitochondria. Our inability to assign functions to the other mitochondrial products arises from a general lack of knowledge about the functions of the different subunit polypeptides of the respiratory and ATPase complexes.…”

Section: Properties Of Mitochondrial Productsmentioning

confidence: 99%

See 3 more Smart Citations

Mitochondrial Genes and Translation Products

Tzagoloff¹,

Macino²

1979

Annu. Rev. Biochem.

245

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Section: Identity Of Mitochondrial Productsmentioning

confidence: 99%

Section: Properties Of Mitochondrial Productsmentioning

confidence: 99%

Section: Properties Of Mitochondrial Productsmentioning

confidence: 99%

Section: Properties Of Mitochondrial Productsmentioning

confidence: 99%

See 2 more Smart Citations

Mitochondrial Genes and Translation Products

Tzagoloff¹,

Macino²

1979

Annu. Rev. Biochem.

245

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“…On the other hand, there are examples of high molecular weight products of mitochondrial protein synthesis obtained under appropriate conditions which are capable of yielding small peptides by various chemical and physical treatments [24,29 -331. For example, Tzagoloff and Akai [30] observed in the yeast Saccharomyces cerevisiae a conversion of a major mitochondrial product of M , 45000 into a peptide of M , 7500 by treatment with chloroform/ methanol or sodium dodecylsulfate at alkaline pH. This peptide was later claimed to be subunit 9 of the ATPase complex [8].…”

Section: Discussionmentioning

confidence: 99%

The Dicyclohexylcarbodiimide-Binding Protein of Rat Liver Mitochondria as a Product of the Mitochondrial Protein Synthesis

1978

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A product of mitochondrial protein synthesis in rat liver mitochondria, characterized by a low molecular weight ( M , < 10000) and an unusually high hydrophobicity, has been identified as the dicyclohexylcarbodiimide-binding protein and as a peptide of the hydrophobic sector of the mitochondrial ATPase complex. The purified protein still possesses the ability to bind dicyclohexylcarbodiimide.Since the first report by Beechey et al. [l] that dicyclohexylcarbodiimide inhibits oxidative phosphorylation, there have been a number of reports on the isolation from mitochondria [2], chloroplasts [3] and bacteria [4,5j, of a small molecular weight protein capable of binding dicyclohexylcarbodiimide irreversibly and probably covalently. The dicyclohexylcarbodiimide-binding protein appears to be a subunit of the hydrophobic sector of the ATPase complex [6]. It is a proteolipid soluble in chloroform/methanol. In spite of a large amount of work on the chemical characterization of the dicyclohexylcarbodiimide-binding protein, little information is available on the biosynthesis of this protein in mitochondria. In Neurospora crassa, the dicyclohexylcarbodiimide-binding protein is synthetized outside of mitochondria on cytoplasmic ribosomes [7j. On the other hand, it has been suggested that in the yeast, Saccharomyces cerevisiae, the smallest component of the oligomycin-sensitive ATPase, subunit 9, which is synthetized on mitochondrial ribosomes, could be the component which interacts with rutamycin and dicyclohexylcarbodiimide [8].In a previous study, two low-molecular-weight products of mitochondrial protein synthesis were isolated from a chloroform/methanol extract of a trichloroacetic acid precipitate of rat liver mitochondria. They were characterized by an unusual hydrophobicity reflected by their behaviour on paper chromatography. Because of their chromatographic properties they were designated as fast-running products. The two products were further separated by thin-layer chromatography and referred to as fast-running Enzyme. ATP phosphohydrolase or ATPase (EC 3.6.1.3) product A and fast-running product B respectively [9]. In this paper, we show that fast-running product B of the mitochondrial protein synthesis is the dicyclohexylcarbodiimide-binding protein. Some of the data have been presented in an abstract form [lo]. MATERIALS AND METHODS Chemicals Procedures for Mitochondria1 PreparationsRat liver mitochondria were isolated from Wistar rats [ l l ] and resuspended in 0.25 M sucrose, 10 mM Tris-HC1, pH 7.4. They were washed twice in 0.25 M sucrose, 1 mM EDTA and 10 mM Tris-HCI, pH 7.4.Beef heart mitochondria were prepared according to Smith [12]. Submitochondrial particles were prepared by sonication of rat liver or beef heart mitochondria after dilution to a concentration of 10-15 mg protein in 0.25 M sucrose, 1 mM EDTA and 10 mM Tris-HC1, pH 7.4. The mitochondrial suspension was exposed to sonic oscillations in a Branson sonifier at 100 W for six periods of 30 s each, separated by 1-min intervals. The temperature ...

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Superoxide Dismutases

Fridovich

1974

Advances in Enzymology - And Related Areas of Molecular Biology

248

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Mitochondrial Products of Yeast Atpase and Cytochrome Oxidase

Cited by 33 publications

References 25 publications

Mitochondrial Genes and Translation Products

Mitochondrial Genes and Translation Products

The Dicyclohexylcarbodiimide-Binding Protein of Rat Liver Mitochondria as a Product of the Mitochondrial Protein Synthesis

Superoxide Dismutases

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