Coherent Properties of the Membranous Systems of Electron Transport Phosphorylation
1983; Springer Nature; Linguagem: Inglês
10.1007/978-3-642-69186-7_17
ISSN0172-6625
AutoresDouglas B. Kell, G. Duncan Hitchens,
Tópico(s)Nanopore and Nanochannel Transport Studies
ResumoIt is now well known that the role of a universal chemical energy currency in living cells is played by the so-called high-energy compound adenosine triphosphate (ATP), whose endergonic synthesis from adenosine diphosphate (ADP) and inorganic phosphate (ΔG0' = + 31 kJ mol-1) permits the cell to store free energy in a kinetically stable chemical form. One source of the free energy necessary to drive this reaction lies in processes such as oxidative metabolism or photosynthetic electron flow, and the overall process of ATP synthesis coupled to electron transfer is thus referred to as electron transport phosphorylation (see e.g. Stryer, 1981, Lehninger, 1982). The question then arises as to the nature of the free energy transfer between the (exergonic) reactions of electron transport and the otherwise endergonic synthesis of ATP. It is usual to encapsulate this question in the form of a scheme (equation 1) in which a 'high energy intermediate', often denoted "∼" ("squiggle"), constitutes the energetic link between electron transport and ATP synthesis; it is the nature of this "∼" that forms the subject of the present considerations.
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