+ Site Statistics
+ Search Articles
+ PDF Full Text Service
How our service works
Request PDF Full Text
+ Follow Us
Follow on Facebook
Follow on Twitter
Follow on LinkedIn
+ Subscribe to Site Feeds
Most Shared
PDF Full Text
+ Translate
+ Recently Requested

The alpha/beta subunit interaction in H(+)-ATPase (ATP synthase). An Escherichia coli alpha subunit mutation (Arg-alpha 296-->Cys) restores coupling efficiency to the deleterious beta subunit mutant (Ser-beta 174-->Phe)



The alpha/beta subunit interaction in H(+)-ATPase (ATP synthase). An Escherichia coli alpha subunit mutation (Arg-alpha 296-->Cys) restores coupling efficiency to the deleterious beta subunit mutant (Ser-beta 174-->Phe)



Journal of Biological Chemistry 269(14): 10265-9



The Ser-beta 174 residue of the Escherichia coli H(+)-ATPase beta subunit has been shown to be near the catalytic site together with Gly-beta 149, Gly-beta 172, Glu-beta 192, and Val-beta 198 (Iwamoto, A., Park, M.-Y., Maeda, M., and Futai, M. (1993) J. Biol. Chem. 268, 3156-3160). In this study, we introduced various residues at position 174 and found that the larger the side chain volume of the residue introduced, the lower the enzyme activity became. The Phe-beta 174 mutant was defective in energy coupling between catalysis and transport, whereas the Leu-beta 174 mutant could couple efficiently, although both mutants had essentially the same ATPase activities (approximately 10% of the wild type). The defective energy coupling of the Phe-beta 174 mutant was suppressed by the second mutation (Arg-alpha 296-->Cys) in the alpha subunit. The Cys-alpha 296/Phe-beta 174 mutant had essentially the same membrane ATPase activity as the Phe-beta 174 single mutant when assayed under the conditions that stabilize the double mutant enzyme. These results indicate the importance of the alpha/beta interaction, especially that between the regions near Arg-alpha 296 and Ser-beta 174, for energy coupling in the H(+)-ATPase. The 2 residues (Ser-beta 174 and Arg-alpha 296) may be located nearby at the interface of the two subunits. About 1 mol of N-[14C]ethylmaleimide could bind to 1 mol of the alpha subunit of Cys-alpha 296/Phe-beta 174 or Cys-alpha 296 mutant ATPase, but could not inhibit the enzyme activity. This is the first intersubunit mutation/suppression approach to ATPase catalysis and its energy coupling.

Please choose payment method:






(PDF emailed within 1 workday: $29.90)

Accession: 047578238

Download citation: RISBibTeXText

PMID: 8144607


Related references

The alpha/beta subunit interaction in H+-ATPase An Escherichia coli alpha subunit mutation restores coupling efficiency to the deleterious beta subunit mutant. Journal of Biological Chemistry 269(14): 10265-10269, 1994

The a/b subunit interaction in H+-ATPase (ATP synthase). An Escherichia coli a subunit mutation (Arg-a296- >Cys) restores coupling efficiency to the deleterious b subunit mutant (Ser-b174- >Phe). The Journal of Biological Chemistry 269: 265-9, 1994

The cysteine introduced into the alpha subunit of the Escherichia coli F-1-ATPase by the mutation alpha-R376C is near the alpha-beta subunit interface and close to a noncatalytic nucleotide binding site. Journal of Biological Chemistry 268(10): 6978-6984, 1993

N-ethylmaleimide-sensitive mutant (beta Val-153-->Cys) Escherichia coli F1-ATPase: cross-linking of the mutant beta subunit with the alpha subunit. Febs Letters 352(2): 243-246, 1994

Conformational changes in the alpha-subunit coupled to binding of the beta 2-subunit of tryptophan synthase from Escherichia coli: crystal structure of the tryptophan synthase alpha-subunit alone. Biochemistry 44(4): 1184-1192, 2005

Subunit communication in the tryptophan synthase alpha 2 beta 2 complex. Effects of beta subunit ligands on proteolytic cleavage of a flexible loop in the alpha subunit. Febs Letters 299(2): 197-200, 1992

Intergenic suppression in a beta subunit mutant with defective assembly in Escherichia coli F1ATPase. Second-site mutation in the alpha subunit. Febs Letters 344(2-3): 187-190, 1994

Mammalian karyopherin alpha 1 beta and alpha 2 beta heterodimers: alpha 1 or alpha 2 subunit binds nuclear localization signal and beta subunit interacts with peptide repeat-containing nucleoporins. Proceedings of the National Academy of Sciences of the United States of America 92(14): 6532-6536, 1995

Cloning, baculovirus expression, and characterization of the alpha subunit of prolyl 4-hydroxylase from the nematode Caenorhabditis elegans. This alpha subunit forms an active alpha beta dimer with the human protein disulfide isomerase/beta subunit. Journal of Biological Chemistry 269(43): 26746-26753, 1994

Escherichia coli F1-ATPase subunit interactions: beta and gamma subunit peptides inhibit in vitro reconstitution of the active alpha beta gamma complex. Archives of Biochemistry and Biophysics 340(1): 36-42, 1997

Sodium ion potassium ion atpase alpha alpha 1 alpha 2 alpha 3 and beta beta 1 beta 2 subunit isoforms reveal regional cellular and subcellular differences along the ocular ciliary epithelium. Investigative Ophthalmology & Visual Science 32(4): 1185, 1991

Identification of alpha-subunit Lys201 and beta-subunit Lys155 at the ATP-binding sites in Escherichia coli F1-ATPase. Febs Letters 233(2): 347-351, 1988

Threonine 183 and adjacent flexible loop residues in the tryptophan synthase alpha subunit have critical roles in modulating the enzymatic activities of the beta subunit in the alpha 2 beta 2 complex. Journal of Biological Chemistry 267(11): 7520-7528, 1992

Threonine 183 and adjacent flexible loop residues in the alpha subunit of tryptophan synthase have critical roles in modulating the enzymatic activities of the beta subunit in the alpha 2 beta 2 complex. Biophysical Journal 61(2 Part 2): A458, 1992

Assembly of the extracellular domain of the Na,K-ATPase beta subunit with the alpha subunit. Analysis of beta subunit chimeras and carboxyl-terminal deletions. Journal of Biological Chemistry 268(32): 24367-24373, 1993