Energy-converting hydrogenases: the link between H2 metabolism and energy conservation

  title={Energy-converting hydrogenases: the link between H2 metabolism and energy conservation},
  author={Marie Charlotte Schoelmerich and Volker M{\"u}ller},
  journal={Cellular and Molecular Life Sciences},
  pages={1461 - 1481}
The reversible interconversion of molecular hydrogen and protons is one of the most ancient microbial metabolic reactions and catalyzed by hydrogenases. A widespread yet largely enigmatic group comprises multisubunit [NiFe] hydrogenases, that directly couple H2 metabolism to the electrochemical ion gradient across the membranes of bacteria and of archaea. These complexes are collectively referred to as energy-converting hydrogenases (Ech), as they reversibly transform redox energy into… 
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Lactate metabolism in strictly anaerobic microorganisms with a soluble NAD+ -dependent L-lactate dehydrogenase.
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Energy-Converting [NiFe] Hydrogenases from Archaea and Extremophiles: Ancestors of Complex I
  • R. Hedderich
  • Biology, Chemistry
    Journal of bioenergetics and biomembranes
  • 2004
This work has shown that members of this hydrogenase family mainly function to provide the cell with reduced ferredoxin with H2 as electron donor in a reaction driven by reverse electron transport and have been designated as energy-converting [NiFe] hydrogenases.
Energy-Converting [NiFe] Hydrogenases: More than Just H2 Activation
These hydrogenases have been designated as energy-converting [NiFe] hydrogenases because of sequence similarity with subunits that form the catalytic core of energy-conserving NADH:quinone oxidoreductases (complex I).
Energy conservation by a hydrogenase-dependent chemiosmotic mechanism in an ancient metabolic pathway
Data demonstrate that the energy-converting hydrogenase in concert with an ATP synthase may be the simplest form of respiration; it combines carbon dioxide fixation with the synthesis of ATP in an ancient pathway.
A Bacterial Electron-bifurcating Hydrogenase*
Spectroscopic analyses revealed that NAD+ and ferredoxin reduction are strictly coupled and that they are reduced in a 1:1 stoichiometry.
Energy conservation by oxidation of formate to carbon dioxide and hydrogen via a sodium ion current in a hyperthermophilic archaeon
Significance We report here that oxidation of formate to CO2 and H2 that operates close to thermodynamic equilibrium is coupled to vectorial H+ and Na+ transport across the cytoplasmic membrane of
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Compelling evidence from sequences and structures indicates that the [NiFe]- and [Fe]-H2ases are phylogenetically distinct classes of proteins, which would be consistent with the phylogenetic distinctiveness of the two classes of H2ases.
A genome-guided analysis of energy conservation in the thermophilic, cytochrome-free acetogenic bacterium Thermoanaerobacter kivui
The thermophilic acetogen T. kivui is an interesting acetogen to be used for the production of biocommodities in industrial micobiology and supported the new classification of acetogens into two groups: Rnf- and Ech-containing acetogens.
The Model [NiFe]-Hydrogenases of Escherichia coli.
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  • Biology
    Advances in microbial physiology
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