Subunit b of the membrane moiety (F0) of ATP synthase (F1F0) from Escherichia coli is indispensable for H+ translocation and binding of the water-soluble F1 moiety.
AUTOR(ES)
Schneider, E
RESUMO
The ATP synthase complex, designated F1F0, of Escherichia coli is composed of a water-soluble portion (F1; membrane-associated ATPase, EC 3.6.1.3) with ATP-hydrolyzing activity and a membrane-integrated part (F0) with H+-translocating activity. F0 is built up from three kinds of subunits (a, b, and c). We have isolated the F0 portion directly from membranes of an E. coli strain (KY 7485) that overproduces the enzyme several fold. Subunit b was extracted from purified F0 by two methods. One method included prolonged incubation of the F0 complex in the presence of trichloroacetate (2.5 M) and the separation of subunit b and an a-c complex by gel filtration. Alternatively, subunit b was extracted by deoxycholate and separated from the a-c complex by hydrophobic-interaction chromatography. Integrated into liposomes, the a-c complex exhibited neither H+ uptake nor binding of F1. However, a functional F0 complex was reconstituted by adding stoichiometric amounts of subunit b to the a-c complex.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=392129Documentos Relacionados
- Defective gamma subunit of ATP synthase (F1F0) from Escherichia coli leads to resistance to aminoglycoside antibiotics.
- All three subunits are required for the reconstitution of an active proton channel (F0) of Escherichia coli ATP synthase (F1F0).
- Targeted mutagenesis of the b subunit of F1F0 ATP synthase in Escherichia coli: Glu-77 through Gln-85.
- Mechanism of Uptake of a Cationic Water-Soluble Pyridinium Zinc Phthalocyanine across the Outer Membrane of Escherichia coli
- Mutations in the delta subunit influence the assembly of F1F0 ATP synthase in Escherichia coli.