Archives of Microbiology

, Volume 193, Issue 12, pp 893–903

Efficient electron transfer from hydrogen to benzyl viologen by the [NiFe]-hydrogenases of Escherichia coli is dependent on the coexpression of the iron–sulfur cluster-containing small subunit

Authors

  • Constanze Pinske
    • Institute for MicrobiologyMartin-Luther University Halle-Wittenberg
  • Sara Krüger
    • Institute for MicrobiologyMartin-Luther University Halle-Wittenberg
  • Basem Soboh
    • Institute for MicrobiologyMartin-Luther University Halle-Wittenberg
  • Christian Ihling
    • Institute of PharmacyMartin-Luther University Halle-Wittenberg
  • Martin Kuhns
    • Institute for MicrobiologyMartin-Luther University Halle-Wittenberg
  • Mario Braussemann
    • Institute for MicrobiologyMartin-Luther University Halle-Wittenberg
  • Monique Jaroschinsky
    • Institute for MicrobiologyMartin-Luther University Halle-Wittenberg
  • Christopher Sauer
    • Institute for MicrobiologyMartin-Luther University Halle-Wittenberg
  • Frank Sargent
    • Division of Molecular MicrobiologyCollege of Life Sciences, University of Dundee
  • Andrea Sinz
    • Institute of PharmacyMartin-Luther University Halle-Wittenberg
    • Institute for MicrobiologyMartin-Luther University Halle-Wittenberg
Original Paper

DOI: 10.1007/s00203-011-0726-5

Cite this article as:
Pinske, C., Krüger, S., Soboh, B. et al. Arch Microbiol (2011) 193: 893. doi:10.1007/s00203-011-0726-5

Abstract

Escherichia coli can both oxidize hydrogen and reduce protons. These activities involve three distinct [NiFe]-hydrogenases, termed Hyd-1, Hyd-2, and Hyd-3, each minimally comprising heterodimers of a large subunit, containing the [NiFe] active site, and a small subunit, bearing iron–sulfur clusters. Dihydrogen-oxidizing activity can be determined using redox dyes like benzyl viologen (BV); however, it is unclear whether electron transfer to BV occurs directly at the active site, or via an iron–sulfur center in the small subunit. Plasmids encoding Strep-tagged derivatives of the large subunits of the three E. coli [NiFe]-hydrogenases restored activity of the respective hydrogenase to strain FTD147, which carries in-frame deletions in the hyaB, hybC, and hycE genes encoding the large subunits of Hyd-1, Hyd-2, and Hyd-3, respectively. Purified Strep-HyaB was associated with the Hyd-1 small subunit (HyaA), and purified Strep-HybC was associated with the Hyd-2 small subunit (HybO), and a second iron–sulfur protein, HybA. However, Strep-HybC isolated from a hybO mutant had no other associated subunits and lacked BV-dependent hydrogenase activity. Mutants deleted separately for hyaA, hybO, or hycG (Hyd-3 small subunit) lacked BV-linked hydrogenase activity, despite the Hyd-1 and Hyd-2 large subunits being processed. These findings demonstrate that hydrogenase-dependent reduction of BV requires the small subunit.

Keywords

[NiFe]-hydrogenaseIron–sulfur clusterElectron transferHydrogen evolutionHydrogen oxidationViologen dyes

Copyright information

© Springer-Verlag 2011