Existence of two different species of mitochondrially translated proteolipids in ATPase complex of yeast mitochondria

“…The proteolipid described here is a membranaus protein which appears tobe a subunit of Fo (Esparza et al, 1981;Macreadie et al, 1982) in eucaryotic cells. No analogous polypeptide occurs in preparations of Fo from &cherichia coli (Negrin et al, 1980;Friedl and Schairer, 1981).…”

Section: Main Features Of This Proteolipidmentioning

confidence: 99%

“…21 500 is the product of the 0/i 2 locus (Macino and Tzagoloff, 1980). There is evidence that a third subunit, translated on mitochondrial ribosomes also belongs to the ATP synthase complex (Esparza et al, 1981;Macreadie et al, 1982). This subunit has an apparent size of 10 kd based on its mobility in SDS-polyacrylamide gels (Orian et al, 1981;Esparza et al, 1981).…”

Section: Introductionmentioning

confidence: 99%

Amino acid sequence of a new mitochondrially synthesized proteolipid of the ATP synthase of Saccharomyces cerevisiae.

Velours¹,

Esparza²,

Hoppe³

et al. 1984

The EMBO Journal

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The purification and the amino acid sequence of a proteolipid translated on ribosomes in yeast mitochondria is reported. This protein, which is a subunit of the A TP synthase, was purified by extraction with chloroform/methanol (2/1) and subsequent chromatography on phosphocellulose and reverse phase h.p.l.c. A mol. wt. of 5500 was estimated by chromatography on Bio-Gel P-30 in 8011/o fonnie acid. The complete amino acid sequence of this protein was determined by automated solid phase Edman degradation of the whole protein and of fragments obtained after cleavage with cyanogen bromide. The sequence analysis indicates a length of 48 amino acid residues. The calculated mol. wt. of 5870 corresponds to the value found by gel chromatography. This polypeptide contains three basic residues and no negatively charged side chain. The three basic residues are clustered at the C terminus. The primary structure of this protein is in full agreement with the predicted amino acid sequence of the putative polypeptide encoded by the mitochondrial aap1 gene recently discovered in Saccharomyces cerevisiae. Moreover, this protein shows 5011/o homology with the amino acid sequence of a putative polypeptide encoded by an unidentified reading frame also discovered near the mitochondrial ATPase subunit 6 genein Aspergillus nidulans.

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Evidence from immunological studies of structure-mechanism relationship of F1 and F1F0

Gautheron¹,

Godinot²

1988

J Bioenerg Biomembr

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Monoclonal and polyclonal antibodies directed against peptides of F1-ATPase of F1F0-ATPase synthase provide new and efficient tools to study structure-function relationships and mechanisms of such complex membrane enzymes. This review summarizes the main results obtained using this approach. Antibodies have permitted the determination of the nature of subunits involved in the complex, their stoichiometry, their organization, neighboring interactions, and vectorial distribution within or on either face of the membrane. Moreover, in a few cases, amino acid sequences exposed on a face of the membrane or buried inside the complex have been identified. Antibodies are very useful for detecting the role of each subunit, especially for those subunits which appear to have no direct involvement in the catalytic mechanism. Concerning the mechanisms, the availability of monoclonal antibodies which inhibit (or activate) ATP hydrolysis or ATP synthesis, which modify nucleotide binding or regulation of activities, which detect specific conformations, etc. brings many new ways of understanding the precise functions. The specific recognition by monoclonal antibodies on the beta subunit of epitopes in the proximity of, or in the catalytic site, gives information on this site. The use of anti-alpha monoclonal antibodies has shown asymmetry of alpha in the complex as already shown for beta. In addition, the involvement of alpha with respect to nucleotide site cooperativity has been detected. Finally, the formation of F1F0-antibody complexes of various masses, seems to exclude the functional rotation of F1 around F0 during catalysis.

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Existence of two different species of mitochondrially translated proteolipids in ATPase complex of yeast mitochondria

Cited by 14 publications

References 27 publications

Afg3p, a mitochondrial ATP‐dependent metalloprotease, is involved in degradation of mitochondrially‐encoded Cox1, Cox3, Cob, Su6, Su8 and Su9 subunits of the inner membrane complexes III, IV and V

Afg3p, a mitochondrial ATP‐dependent metalloprotease, is involved in degradation of mitochondrially‐encoded Cox1, Cox3, Cob, Su6, Su8 and Su9 subunits of the inner membrane complexes III, IV and V

Amino acid sequence of a new mitochondrially synthesized proteolipid of the ATP synthase of Saccharomyces cerevisiae.

Evidence from immunological studies of structure-mechanism relationship of F1 and F1F0

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