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Archives of Microbiology

, Volume 178, Issue 6, pp 437–442 | Cite as

Effect of redox potential on activity of hydrogenase 1 and hydrogenase 2 in Escherichia coli

  • Tatyana V. Laurinavichene
  • Nikolai A. Zorin
  • Anatoly A. Tsygankov
Original Paper

Abstract.

This report elucidates the distinctions of redox properties between two uptake hydrogenases in Escherichia coli. Hydrogen uptake in the presence of mediators with different redox potential was studied in cell-free extracts of E. coli mutants HDK103 and HDK203 synthesizing hydrogenase 2 or hydrogenase 1, respectively. Both hydrogenases mediated H2 uptake in the presence of high-potential acceptors (ferricyanide and phenazine methosulfate). H2 uptake in the presence of low-potential acceptors (methyl and benzyl viologen) was mediated mainly by hydrogenase 2. To explore the dependence of hydrogen consumption on redox potential of media in cell-free extracts, a chamber with hydrogen and redox (Eh) electrodes was used. The mutants HDK103 and HDK203 exhibited significant distinctions in their redox behavior. During the redox titration, maximal hydrogenase 2 activity was observed at the Eh below –80 mV. Hydrogenase 1 had maximum activity in the Eh range from +30 mV to +110 mV. Unlike hydrogenase 2, the activated hydrogenase 1 retained activity after a fast shift of redox potential up to +500 mV by ferricyanide titration and was more tolerant to O2. Thus, two hydrogenases in E. coli are complementary in their redox properties, hydrogenase 1 functioning at higher redox potentials and/or at higher O2 concentrations than hydrogenase 2.

Escherichia coli Hydrogenase 1 Hydrogenase 2 Redox titration Hydrogen consumption 

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Copyright information

© Springer-Verlag 2002

Authors and Affiliations

  • Tatyana V. Laurinavichene
    • 1
  • Nikolai A. Zorin
    • 1
  • Anatoly A. Tsygankov
    • 1
  1. 1.Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino, Moscow region, 142290, Russia

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