Characterization of the binding of Fe(III) to F1ATPase from bovine heart mitochondria

FEBS Letters

Di Pancrazio, Francesca¹  Lippe, Giovanna¹  Polizio, Francesca²  Dabbeni-Sala, Federica⁴  Desideri, Alessandro²  Bortolotti, Nadia³  Mavelli, Irene¹ 

[1] Department of Biomedical Sciences and Technologies, University of Udine, Via Gervasutta 48, Udine, Italy;INFM-Department of Biology, University of Rome ‘Tor Vergata’, Via della Ricerca Scientifica, Rome, Italy;Cattedra di Patologia Clinica, Università di Udine, Via Gervasutta 48, Udine, Italy;Department of Pharmacology, University of Padua, Largo Meneghetti, Paduda, Italy

关键词: F1ATPase;    Metal-binding site;    Electron paramagnetic resonance;    Iron;    EPR;    electron paramagnetic resonance;    FSBA;    5′-p-fluorosulfonylbenzoyladenosine;    CDTA;    trans-1;    2-diaminocyclohexane-N;    N;    N′;    N′-tetraacetic acid;    HPLC;    high-performance liquid;   

DOI  :  10.1016/0014-5793(95)01517-5

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The binding of Fe(III) to F₁ATPase purified from beef heart mitochondria has been characterized by chemical analyses and EPR spectroscopy. F₁ATPase binds 2 of Fe(III)/mol of protein selectively in the presence of saturating concentrations of ATP. In the absence of nucleotides or in the presence of either saturating ADP or limiting ATP concentrations, the enzyme binds 1 equivalent of Fe(III). F₁ATPase pretreated with 5′-p-fluorosulfonylbenzoyladenosine, that selectively modifies the noncatalytic sites, binds only 1 mol of Fe(III)/mol of protein in the presence of either saturating ATP or ADP. Fe(III)-loaded F₁ATPase containing either 1 or 2 equivalents of Fe(III) show identical EPR signals at g = 4.3. The signals are not perturbed by the binding of nucleotides to the enzyme while they are altered by phosphate addition. These results indicate that F₁ATPase contains two distinct Fe(III)-binding sites, which differ from nucleotide-binding sites, and that one of these sites is opened up for Fe(III) uptake by conformational changes induced by binding of ATP to the loose non-catalytic site.

【 授权许可】

Unknown