Cell Biochemistry and Biophysics

, Volume 41, Issue 3, pp 357–365

Hydrogenase 3 but not hydrogenase 4 is major in hydrogen gas production by Escherichia coli formate hydrogenlyase at acidic pH and in the presence of external formate

  • Nelli Mnatsakanyan
  • Karine Bagramyan
  • Armen Trchounian
Original Article

DOI: 10.1385/CBB:41:3:357

Cite this article as:
Mnatsakanyan, N., Bagramyan, K. & Trchounian, A. Cell Biochem Biophys (2004) 41: 357. doi:10.1385/CBB:41:3:357

Abstract

Fermenting Escherichia coli is able to produce formate and molecular hydrogen (H2) when grown on glucose. H2 formation is possessed by two hydrogenases, 3 (Hyd-3) and 4 (Hyd-4), those, in conjunction with formate dehydrogenase H (Fdh-H), constitute distinct membrane-associated formate hydrogenylases. At slightly alkaline pH (pH 7.5), the production of H2 was found to be dependent on Hyd-4 and the F0F1-adenosine triphosphate (ATPase), whereas external formate increased the activity of Hyd-3. In this study with cells grown without and with external formate H2 production dependent on pH was investigated. In both types of cells, H2 production was increased after lowering of pH. At acidic pH (pH 5.5), this production became insensitive either to N,N′-dicyclohexylcarbodiimide or to osmotic shock and it became largely dependent on Fdh-H and Hyd-3 but not Hyd-4 and the F0F1-ATPase. The results indicate that Hyd-3 has a major role in H2 production at acidic pH independently on the F0F1-ATPase.

Index Entries

Formate hydrogenlyasepHEscherichia coli

Copyright information

© Humana Press Inc 2004

Authors and Affiliations

  • Nelli Mnatsakanyan
    • 1
  • Karine Bagramyan
    • 1
  • Armen Trchounian
    • 1
  1. 1.Department of Biophysics of the Biological FacultyYerevan State UniversityYerevanArmenia