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Factor B and the mitochondrial ATP synthase complex.

Grigory I Belogrudov·Youssef Hatefi
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Abstract

Factor B is a subunit of the mammalian ATP synthase complex, whose existence has been controversial. This paper describes the molecular and functional properties of a recombinant human factor B, which when added to bovine submitochondrial particles depleted of their factor B restores the energy coupling activity of the ATP synthase complexes. The mature human factor B has 175 amino acids and a molecular mass of 20,341 Da. The preparation is water-soluble, monomeric, and is inactivated by monothiol- and especially dithiol-modifying reagents, probably reacting at its cysteine residues Cys-92 and Cys-94. A likely factor B gene composed of 5 exons has been identified on chromosome 14q21.3, and the functional role of factor B in the mammalian ATP synthase complex has been discussed.

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Amino Acid SequenceAnimalsBase SequenceBinding SitesCattleChromosome MappingCloning, MolecularCysteineElectron TransportExonsHumansKineticsMitochondria, HeartMitochondrial Proton-Translocating ATPasesMolecular Sequence DataMolecular WeightOligomycinsProtein SubunitsRecombinant ProteinsSulfhydryl CompoundsJournal Article

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Grigory I Belogrudov, Youssef Hatefi. 2001-12-14. Factor B and the mitochondrial ATP synthase complex.. https://doi.org/10.1074/jbc.m111256200

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