title: H2 conversion in the presence of O2 as performed by the membrane-bound [NiFe]-hydrogenase of Ralstonia eutropha.
abstract: [NiFe]-hydrogenases catalyze the oxidation of H(2) 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. H(2) catalysis of most [NiFe]-hydrogenases is sensitive to dioxygen. However, some bacteria contain hydrogenases that activate H(2) even in the presence of O(2). There is now compelling evidence that O(2) affects hydrogenase on three levels: 1) H(2) catalysis, 2) hydrogenase maturation, and 3) H(2)-mediated signal transduction. Herein, we summarize the genetic, biochemical, electrochemical, and spectroscopic properties related to the O(2) 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 O(2)-tolerant hydrogenases.
authors.affiliation: Department of Microbiology, Humboldt-Universität zu Berlin, Chausseestrasse 117, 10115 Berlin, Germany. oliver.lenz@cms.hu-berlin.de
authors.forename: Oliver
authors.initials: O
authors.lastname: Lenz
authors.forename: Marcus
authors.initials: M
authors.lastname: Ludwig
authors.forename: Torsten
authors.initials: T
authors.lastname: Schubert
authors.forename: Ingmar
authors.initials: I
authors.lastname: Bürstel
authors.forename: Stefanie
authors.initials: S
authors.lastname: Ganskow
authors.forename: Tobias
authors.initials: T
authors.lastname: Goris
authors.forename: Alexander
authors.initials: A
authors.lastname: Schwarze
authors.forename: Bärbel
authors.initials: B
authors.lastname: Friedrich
mesh_terms: D055162:Biocatalysis; D020134:Catalytic Domain; D020118:Cupriavidus necator / Q000201:enzymology*; D006859:Hydrogen / Q000737:chemistry / Q000378:metabolism*; D006864:Hydrogenase / Q000378:metabolism*; D010084:Oxidation-Reduction; D010100:Oxygen / Q000737:chemistry*
chemical_list: D006859:Hydrogen; C043296:nickel-iron hydrogenase; D006864:Hydrogenase; D010100:Oxygen