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Hydrogen evolution by photobleached Anabaena cylindrica
1Institute of Biophysics, Biological Research Center, Hungarian Academy of Sciences, P.O. Box 521, H-6701, Szeged, Hungary.
Planta
|November 27, 2013
Summary
Photobleached Anabaena cylindrica filaments produce significantly more hydrogen due to induced reversible hydrogenase activity. This enhanced hydrogen evolution increases light energy conversion efficiency, with water as a potential electron source.
Area of Science:
- Biotechnology
- Photosynthesis Research
- Algal Physiology
Background:
- Anabaena cylindrica, a heterocystous cyanobacterium, is known for its nitrogenase activity.
- Photobleaching induces changes in algal cell physiology, including pigment accumulation.
Purpose of the Study:
- To investigate hydrogen evolution in photobleached Anabaena cylindrica.
- To understand the mechanisms behind enhanced hydrogen production in modified algal filaments.
Main Methods:
- Inducing photobleaching in Anabaena cylindrica filaments.
- Measuring hydrogen evolution rates.
- Assessing nitrogenase activity.
- Investigating the effect of DCMU (3-(3',4'-dichlorophenyl)-1,1-dimethyl urea) on hydrogen evolution.
Main Results:
- Photobleached (yellow) filaments exhibited significantly higher hydrogen production compared to normal (green) filaments.
- Nitrogenase activity increased to a lesser extent than hydrogen evolution.
- Reversible hydrogenase activity was induced in photobleached filaments, contributing to excess hydrogen.
- DCMU inhibited hydrogen evolution in yellow filaments, suggesting water as an electron source.
- Light energy conversion efficiency for H2 evolution increased from 0.3% to 1.5-2%.
Conclusions:
- Induced reversible hydrogenase activity in photobleached Anabaena cylindrica is responsible for enhanced hydrogen evolution.
- Water serves as a potential electron donor for this hydrogenase.
- The presence of reversible hydrogenase significantly improves the efficiency of light energy conversion for hydrogen production.
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