The biocatalytic effect of Halobacterium halobium on photoelectrochemical hydrogen production

Sediroglu, V
Eroglu, I
Yucel, M
Turker, L
Gündüz, Ufuk
Hydrogen gas can be produced electrochemically by leading a current through two electrodes immersed in a NaCl solution. Bacteriorhodopsin (BR) a protein found in the purple membrane of Halobacterium halobium, is known to pump protons across the membrane upon illumination. In this study, the effect of BR on photoelectrochemical hydrogen production was investigated. A batch type bio-photoelectrochemical reactor was designed and constructed. The photoelectrochemical hydrogen production experiments were performed with free H. halobium packed cells or immobilised H. halobium cells. The cells were either immobilised in polyacrylamide gel (PAG) or on cellulose acetate membrane (CAM). Experiments were also performed with purple membrane fragments of H. halobium immobilised on cellulose acetate membrane. It was found that the presence of bacteriorhodopsin (BR) in the reactor enhances the hydrogen production rate upon illumination. Immobilisation increased the amount of hydrogen produced per mole of BR. Compared to control experiments without BR, the power requirement of the photoelectrochemical reactor per amount of hydrogen produced decreased fourfold when purple membrane fragments immobilised on CAM were used. The presence of BR regulates the pH of the system, increases the hydrogen production rate and causes light-induced proton dissociation, which lowers the electrical power requirement for the electrochemical conversion.


The effect of Halobacterium halobium on photoelectrochemical hydrogen production
Sediroglu, V; Yucel, M; Gündüz, Ufuk; Turker, L; Eroğlu, İnci (1997-06-26)
A bio-photoelectrochemical (bio-PEC) reactor containing the photosynthetic bacterium Halobacterium halobium has been constructed. H. halobium contains a retinal protein, bacteriorhodopsin, in its purple membrane that gives protons upon illumination. In this system, the biocatalytic effect of bacteriorhodopsin on photoelectrochemical hydrogen production was determined.
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Citation Formats
V. Sediroglu, I. Eroglu, M. Yucel, L. Turker, and U. Gündüz, “The biocatalytic effect of Halobacterium halobium on photoelectrochemical hydrogen production,” JOURNAL OF BIOTECHNOLOGY, pp. 115–124, 1999, Accessed: 00, 2020. [Online]. Available: