Molecular aspects of proton/electron and metabolite supply for chloroplast hydrogenase activity in green algae

• Applicant: Professor Dr. Olaf Kruse
• Subject Area: Plant Genetics and Genomics
• Term: from 2006 to 2012
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 28648222

Plants and cyanobacteria use photosynthesis to convert solar energy into chemical energy. In nature, the chemical energy is stored in a diverse range of biopolymers. Certain green algae have evolved the additional ability to use solar energy and hydrogenase (H2ase) enzymes to produce H2 from H2O, with clear implications for production of new clean fuels for the future. The aim of this project is to define key molecular mechanisms controlling photon, proton (H+) and electron (e-) flow during photosynthetic H2 production in the green algae C. reinhardtii. The programme consists of six modules and builds on a high H2 producing mutant (~2% photon conversion efficiency). 1. LHC antenna engineering will be used to establish the correlation between antenna size and photosynthetic efficiency. 2. The relevance of feeding hydrogenases with external H+ and e- will be investigated by construction of sugar transporter mutants. 3. Alternative oxidase will be overexpressed to evaluate the role of cellular O2 concentrations for hydrogenase activity. 4. New genes involved in H+ and e- supply to the hydrogenases will be identified and analysed by macroarray and microarray studies. 5. Phylogenetic analysis will be applied to identify marine algae with HydA-type hydrogenases. 6. Physiological parameters will be evaluated concerning their influence on hydrogenase activity.

• DFG Programme: Research Grants
• International Connection: Australia
• Participating Person: Ben Hankamer