Application of energy conversion apparatus consisting of photosystem I complex fused with tailor-made peptide tag

2016 Fiscal Year Final Research Report

• Project/Area Number: 15K14551
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Plant molecular biology/Plant physiology
• Research Institution: Okayama University
• Principal Investigator: Takahashi Yuichiro 岡山大学, 異分野基礎科学研究所, 教授 (50183447)
• Co-Investigator(Renkei-kenkyūsha): IMANAKA Hiroyuki 岡山大学, 大学院自然科学研究科, 助教 (10379711) ; 近藤 正晴 名古屋工業大学, 工学研究科, 助教 (20571219)
• Project Period (FY): 2015-04-01 – 2017-03-31
• Keywords: 光合成 / 光化学系I / 葉緑体形質転換 / 葉緑体電池 / アフィニティータグ

Outline of Final Research Achievements

We have developed a chloroplast battery cell which consists of photosynthetic proteins bound to an electrode and produces electricity under illumination. Peptide tags (Au-tags), which have an affinity to gold electrodes, have been screened by the bio-panning method using T7 bacteriophage. We genetically fused the resulting tags to one of the photosystem I (PSI) reaction center proteins and expressed it in the chloroplast of the green alga Chlamydomonas reinhardtii. The PSI complex containing an Ag-tag was purified and was bound to the electrode, resulting in the chloroplast battery cell. We measured electricity of the chloroplast battery cells with wild-type and Au-tag fused PSI complexes in the presence of artificial electron donors under illumination. It was found that only the chloroplast battery cell of Au-tagged PSI complex exhibited electricity. In conclusion, our strategy to use affinity peptide tag to bind PSI complex on the electrode is effective and useful.

Free Research Field

植物生理学