title: On the universal core of bioenergetics.
abstract: Living cells are able to harvest energy by coupling exergonic electron transfer between reducing and oxidising substrates to the generation of chemiosmotic potential. Whereas a wide variety of redox substrates is exploited by prokaryotes resulting in very diverse layouts of electron transfer chains, the ensemble of molecular architectures of enzymes and redox cofactors employed to construct these systems is stunningly small and uniform. An overview of prominent types of electron transfer chains and of their characteristic electrochemical parameters is presented. We propose that basic thermodynamic considerations are able to rationalise the global molecular make-up and functioning of these chemiosmotic systems. Arguments from palaeogeochemistry and molecular phylogeny are employed to discuss the evolutionary history leading from putative energy metabolisms in early life to the chemiosmotic diversity of extant organisms. Following the Occam's razor principle, we only considered for this purpose origin of life scenarios which are contiguous with extant life. This article is part of a Special Issue entitled: The evolutionary aspects of bioenergetic systems.
authors.affiliation: Laboratoire de Bioénergétique et Ingénierie des Protéines UMR 7281 CNRS/AMU, FR3479, F-13402 Marseille Cedex 20, France. schoepp@imm.cnrs.fr
authors.forename: Barbara
authors.initials: B
authors.lastname: Schoepp-Cothenet
authors.forename: Robert
authors.initials: R
authors.lastname: van Lis
authors.forename: Ariane
authors.initials: A
authors.lastname: Atteia
authors.forename: Frauke
authors.initials: F
authors.lastname: Baymann
authors.forename: Line
authors.initials: L
authors.lastname: Capowiez
authors.forename: Anne-Lise
authors.initials: AL
authors.lastname: Ducluzeau
authors.forename: Simon
authors.initials: S
authors.lastname: Duval
authors.forename: Felix
authors.initials: F
authors.lastname: ten Brink
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Russell
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Nitschke
mesh_terms: D000255:Adenosine Triphosphate / Q000096:biosynthesis; D004579:Electron Transport; D004734:Energy Metabolism; D013816:Thermodynamics
chemical_list: D000255:Adenosine Triphosphate