Comprehensive analysis of molecular interaction of ferredoxin and enzymes involved in redox metabolisms in chloroplast

2015 Fiscal Year Final Research Report

• Project/Area Number: 24370021
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Plant molecular biology/Plant physiology
• Research Institution: Osaka University
• Principal Investigator: Hase Toshiharu 大阪大学, たんぱく質研究所, 教授 (00127276)
• Co-Investigator(Kenkyū-buntansha): IKEGAMI Takahisa 横浜市立大学, 生命医学研究科, 教授 (20283939)
• Co-Investigator(Renkei-kenkyūsha): KURISU Genji 大阪大学, 蛋白質研究所, 教授 (90294131)
• Project Period (FY): 2012-04-01 – 2016-03-31
• Keywords: 葉緑体 / レドックス代謝 / フェレドキシン / 酸化還元酵素 / 分子間相互作用

Outline of Final Research Achievements

We have been studying electron transfer between Fd and these enzymes by X-ray crystallography, NMR analysis and isothermal calorimetry to obtain an insight into electron partitioning in chloroplasts. In all cases, their protein-protein interactions are not so strong with Kd values around micro-molar to several tens micro-molar; a set of positively charged residues of the partner enzymes is closed to acidic residues of Fd in a spatially matching manner to produce an electrostatic interaction force. Whole acidic surface of Fd is not utilized for complex formation with partner enzymes and the interaction region appears to be at least partly unique for each enzyme. This topological variety of the molecular recognition between Fd and partner enzymes would be significant for function of Fd as a hub protein in a network of redox metabolisms.We further found the intermolecular interaction of some Fd-dependent enzymes with Fd varied when each enzyme was bound to their substrate.

Free Research Field

植物生化学