2012 Fiscal Year Final Research Report
Torque generation mechanism of F1-ATPase probed by site-specificand reaction-specific single-molecule manipulation
| Project/Area Number |
22247025
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| Research Category |
Grant-in-Aid for Scientific Research (A)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Biophysics
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| Research Institution | The University of Tokyo |
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Principal Investigator |
NOJI Hiroyuki 東京大学, 大学院・工学系研究科, 教授 (00343111)
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| Co-Investigator(Kenkyū-buntansha) |
IINO Ryota 東京大学, 大学院・工学系研究科, 講師 (70403003)
TABATA Kazuhito 東京大学, 大学院・工学系研究科, 助教 (50403001)
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| Project Period (FY) |
2010 – 2012
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| Keywords | 1 分子操作 / 1 分子計測 / 分子モーター |
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| Research Abstract |
We determined the rate constants and equilibrium constants of catalytic reactions on F1-ATPase as a function of rotary angle by manipulating individual F1 molecules. The results show ATP-binding process is the major torque-generating step. A novel single-molecule imaging system using polarized scattering light from a gold nanorod that has high spatiotemporal resolution was established to visualize the conformational change of the subunit, the torque-generating unit of F1. It was revealed that the subunit makes a power-stroke type conformational change. High-speed AFM was applied to visualize the conformational change of the subunit in the isolated stator ring with three subunits. subunits showed highly cooperative conformational transition, propagating the conformational state in the anticlockwise direction as the same as the rotor rotation.This finding means that the structural basis is programmed in the stator ring.
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