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

✍ Scribed by Oliver Lenz; Marcus Ludwig; Torsten Schubert; Ingmar Bürstel; Stefanie Ganskow; Tobias Goris; Alexander Schwarze; Bärbel Friedrich

• Book ID: 102810036
• Publisher: John Wiley and Sons
• Year: 2010
• Tongue: English
• Weight: 841 KB
• Volume: 11
• Category: Article
• ISSN: 1439-4235
• DOI: 10.1002/cphc.200901002

✦ Synopsis

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.