Bioenergetic cost of making an adenosine triphosphate molecule in animal mitochondria.

TitleBioenergetic cost of making an adenosine triphosphate molecule in animal mitochondria.
Publication TypeJournal Article
Year of Publication2010
AuthorsWatt, IN, Montgomery, MG, Runswick, MJ, Leslie, AGW, Walker, JE
JournalProc Natl Acad Sci U S A
Volume107
Issue39
Pagination16823-7
Date Published2010 Sep 28
ISSN1091-6490
KeywordsAdenosine Diphosphate, Adenosine Triphosphate, Amino Acid Sequence, Animals, Catalysis, Catalytic Domain, Cattle, Energy Metabolism, Mitochondria, Molecular Sequence Data, Proton-Translocating ATPases
Abstract

The catalytic domain of the F-ATPase in mitochondria protrudes into the matrix of the organelle, and is attached to the membrane domain by central and peripheral stalks. Energy for the synthesis of ATP from ADP and phosphate is provided by the transmembrane proton-motive-force across the inner membrane, generated by respiration. The proton-motive force is coupled mechanically to ATP synthesis by the rotation at about 100 times per second of the central stalk and an attached ring of c-subunits in the membrane domain. Each c-subunit carries a glutamate exposed around the midpoint of the membrane on the external surface of the ring. The rotation is generated by protonation and deprotonation successively of each glutamate. Each 360° rotation produces three ATP molecules, and requires the translocation of one proton per glutamate by each c-subunit in the ring. In fungi, eubacteria, and plant chloroplasts, ring sizes of c(10)-c(15) subunits have been observed, implying that these enzymes need 3.3-5 protons to make each ATP, but until now no higher eukaryote has been examined. As shown here in the structure of the bovine F(1)-c-ring complex, the c-ring has eight c-subunits. As the sequences of c-subunits are identical throughout almost all vertebrates and are highly conserved in invertebrates, their F-ATPases probably contain c(8)-rings also. Therefore, in about 50,000 vertebrate species, and probably in many or all of the two million invertebrate species, 2.7 protons are required by the F-ATPase to make each ATP molecule.

DOI10.1073/pnas.1011099107
Alternate JournalProc. Natl. Acad. Sci. U.S.A.
Citation Key10.1073/pnas.1011099107
PubMed ID20847295
PubMed Central IDPMC2947889
Grant ListMC_U105184325 / / Medical Research Council / United Kingdom
MC_U105663150 / / Medical Research Council / United Kingdom
/ / Medical Research Council / United Kingdom