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

植物和蓝藻利用光合作用将太阳能转化为化学能。在自然界中，化学能储存在各种生物聚合物中。某些绿藻已经进化出利用太阳能和氢酶(H2 Ase)从H2O中生产氢气的额外能力，这对未来生产新的清洁燃料具有明显的影响。本项目的目的是确定在绿藻C.reinhardtii光合氢产生过程中控制光子、质子(H+)和电子(e-)流动的关键分子机制。该计划由六个模块组成，建立在一个高产氢突变体(~2%的光子转换效率)的基础上。1.将利用LHC天线工程来建立天线尺寸与光合作用效率之间的关系。2.通过构建糖转运蛋白突变体来研究补给氢酶与外源H+和e-的相关性。3.交替氧化酶将被过度表达，以评估细胞内O2浓度对氢酶活性的作用。4.将通过大芯片和微阵列研究来确定和分析与氢酶的H+和e-供应有关的新基因。5.系统发育分析将用于鉴定具有HydA型氢酶的海洋藻类。6.评估生理参数对氢酶活性的影响。

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.