title: An ancient pathway combining carbon dioxide fixation with the generation and utilization of a sodium ion gradient for ATP synthesis.
abstract: Synthesis of acetate from carbon dioxide and molecular hydrogen is considered to be the first carbon assimilation pathway on earth. It combines carbon dioxide fixation into acetyl-CoA with the production of ATP via an energized cell membrane. How the pathway is coupled with the net synthesis of ATP has been an enigma. The anaerobic, acetogenic bacterium Acetobacterium woodii uses an ancient version of this pathway without cytochromes and quinones. It generates a sodium ion potential across the cell membrane by the sodium-motive ferredoxin:NAD oxidoreductase (Rnf). The genome sequence of A. woodii solves the enigma: it uncovers Rnf as the only ion-motive enzyme coupled to the pathway and unravels a metabolism designed to produce reduced ferredoxin and overcome energetic barriers by virtue of electron-bifurcating, soluble enzymes.
authors.affiliation: Göttingen Genomics Laboratory, Institute for Microbiology and Genetics, Georg August University, Göttingen, Germany.
authors.forename: Anja
authors.initials: A
authors.lastname: Poehlein
authors.forename: Silke
authors.initials: S
authors.lastname: Schmidt
authors.forename: Anne-Kristin
authors.initials: AK
authors.lastname: Kaster
authors.forename: Meike
authors.initials: M
authors.lastname: Goenrich
authors.forename: John
authors.initials: J
authors.lastname: Vollmers
authors.forename: Andrea
authors.initials: A
authors.lastname: Thürmer
authors.forename: Johannes
authors.initials: J
authors.lastname: Bertsch
authors.forename: Kai
authors.initials: K
authors.lastname: Schuchmann
authors.forename: Birgit
authors.initials: B
authors.lastname: Voigt
authors.forename: Michael
authors.initials: M
authors.lastname: Hecker
authors.forename: Rolf
authors.initials: R
authors.lastname: Daniel
authors.forename: Rudolf K
authors.initials: RK
authors.lastname: Thauer
authors.forename: Gerhard
authors.initials: G
authors.lastname: Gottschalk
authors.forename: Volker
authors.initials: V
authors.lastname: Müller
mesh_terms: D045855:Acetobacterium / Q000235:genetics / Q000378:metabolism*; D000105:Acetyl Coenzyme A / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000096:biosynthesis*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D053898:Biosynthetic Pathways; D057486:Carbon Cycle; D002245:Carbon Dioxide / Q000378:metabolism*; D002462:Cell Membrane / Q000378:metabolism; D004734:Energy Metabolism; D005288:Ferredoxins / Q000378:metabolism; D016680:Genome, Bacterial / Q000235:genetics; D008954:Models, Biological; D010084:Oxidation-Reduction; D010088:Oxidoreductases / Q000235:genetics / Q000378:metabolism; D012964:Sodium / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D005288:Ferredoxins; D002245:Carbon Dioxide; D000105:Acetyl Coenzyme A; D000255:Adenosine Triphosphate; D012964:Sodium; D010088:Oxidoreductases; C028878:ferredoxin-NAD+ reductase