H2 Conversion in the Presence of O2 as Performed by the Membrane-Bound [NiFe]-Hydrogenase of Ralstonia eutropha

• Published in: Chemphyschem 2010-04, Vol.11 (6), p.1107-1119
• Main Authors: Lenz, Oliver, Ludwig, Marcus, Schubert, Torsten, Bürstel, Ingmar, Ganskow, Stefanie, Goris, Tobias, Schwarze, Alexander, Friedrich, Bärbel
• Format: Article
• Language: English
• Subjects: Biocatalysis; Biological and medical sciences; Catalysis; Catalytic Domain; Cell physiology; Chemistry; Colloidal state and disperse state; Cupriavidus necator - enzymology; Exact sciences and technology; Fundamental and applied biological sciences. Psychology; General and physical chemistry; hydrogen; Hydrogen - chemistry; Hydrogen - metabolism; hydrogen technology; Hydrogenase - metabolism; hydrogenases; Mechanisms. Catalysis. Electron transfer. Models; Membranes; metal-cofactor assembly; Molecular and cellular biology; Molecular biophysics; Oxidation-Reduction; oxygen; Oxygen - chemistry; Physical chemistry in biology; Ralstonia eutropha; Signal transduction; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry
• ISSN: 1439-4235; 1439-7641; 1439-7641
• DOI: 10.1002/cphc.200901002

[NiFe]‐hydrogenases catalyze the oxidation of H2 to protons and electrons. This reversible reaction is based on a complex interplay of metal cofactors including the Ni–Fe active site and several [Fe–S] clusters. H2 catalysis of most [NiFe]‐hydrogenases is sensitive to dioxygen. However, some bacteria contain hydrogenases that activate H2 even in the presence of O2. There is now compelling evidence that O2 affects hydrogenase on three levels: 1) H2 catalysis, 2) hydrogenase maturation, and 3) H2‐mediated signal transduction. Herein, we summarize the genetic, biochemical, electrochemical, and spectroscopic properties related to the O2 tolerance of hydrogenases resident in the facultative chemolithoautotroph Ralstonia eutropha H16. A focus is given to the membrane‐bound [NiFe]‐hydogenase, which currently represents the best‐characterized member of O2‐tolerant hydrogenases. Oxygen‐tolerant hydrogenases: The inherent properties by which membrane‐bound [NiFe]‐hydrogenases of aerobic H2‐oxidizing microorganisms are able to catalyze H2 conversion in the presence of molecular oxygen are discussed.