Identification of an uncoupling mutation affecting the b subunit of F1F0 ATP synthase in Escherichia coli

FEBS Letters

Ketchum, Christian J²  Nakamoto, Robert K²  Sorgen, Paul L¹  Caviston, Tamara L¹  Cain, Brian D¹ 

[1] Department of Biochemistry and Molecular Biology, Box 100245, University of Florida, Gainesville, FL 32610, USA;Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, VA 22906-0011, USA

关键词: F1F0 ATP synthase;    Proton translocation;    LBG;    Luria broth supplemented with glucose;    IPTG;    Isopropyl-1-thio-β-d-galactoside;    Ap;    ampicillin;    Cm;    chloramphenicol;    PCR;    polymerase chain reaction;    ACMA;    9-amino-6-chloro-2-methoxyacridine;    CCCP;    carbonyl cyanide-m-chlorophenylhydrazone;   

DOI  :  10.1016/S0014-5793(98)00597-3

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

A specific b subunit arginine, b _Arg-36 in Escherichia coli, displays evolutionary conservation among bacterial F₁F₀ ATP synthases. Site-directed mutagenesis was used to generate a collection of mutations affecting b _Arg-36. The phenotype differed depending upon the substitution, and the b _Arg-36→Glu and b _Arg-36→Ile substitutions virtually abolished enzyme function. Although the total amounts of F₁F₀ ATP synthase present in the membranes prepared from mutant strains were reduced, the primary effect of the b _Arg-36 substitutions was on the activities of the intact enzyme complexes. The most interesting result was that the b _Arg-36→Glu substitution results in the uncoupling of a functional F₀ from F₁ ATP hydrolysis activity.

【 授权许可】

Unknown